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Palm OS SDK Reference

Palm Logo 54 Net Library

This chapter describes the API available in the net library and its Berkeley sockets equivalents. The header file NetMgr.h declares the net library API. The chapter covers:

For more information on the net library, see the chapter "Network Communication" in the Palm OS Programmer's Companion.


IMPORTANT: Applications cannot directly use the net library to make wireless connections. Use the INetLib for wireless connections.

Net Library Data Structures

NetHostInfoBufType

The NetHostInfoBufType struct contains information about a host. The NetHostInfoType struct, which maps to the hostent struct, points to fields in this struct for its information.

typedef struct {
    NetHostInfoType hostInfo;
    Char name[netDNSMaxDomainName+1];
    Char * aliasList[netDNSMaxAliases+1];
    Char aliases[netDNSMaxAliases]
[netDNSMaxAliases+1];
    NetIPAddr* addressList[netDNSMaxAddresses];
    NetIPAddr address[netDNSMaxAddresses];
} NetHostInfoBufType, *NetHostInfoBufPtr;

Field Descriptions

hostInfo A NetHostInfoType struct, which maps to the Berkeley UNIX sockets hostent structure.
name Official host name.
aliasList aliases An array of aliases for the host name.
addressList address An array of pointers to 32-bit IP addresses in host byte order.

NetHostInfoType

The NetHostInfoType structure maps to the Berkeley UNIX sockets hostent structure. It is defined as follows:

typedef struct {
    Char * nameP;
    Char ** nameAliasesP;
    UInt16 addrType;
    UInt16 addrLen;
    UInt8 ** addrListP;
} NetHostInfoType, *NetHostInfoPtr;

Field Descriptions

nameP Official host name.
nameAliasesP An array of aliases for the host name.
addrType The type of the return addresses. See NetSocketAddrEnum.
addrLen The length in bytes of the return addresses.
addrListP An array of pointers to addresses in host byte order.

NetServInfoBufType

The NetServInfoBufType struct contains information about a service. The NetServInfoType struct, which maps to the servent struct, points to fields in this struct for much of its information.

struct {
    NetServInfoType servInfo;
    Char name[netServMaxName+1];
    Char * aliasList[netServMaxAliases+1];
    Char aliases[netServMaxAliases] [netServMaxName];
    Char protoName[netProtoMaxName+1];
    UInt8 reserved;
} NetServInfoBufType, *NetServInfoBufPtr;

Field Descriptions

servInfo A NetServInfoType struct, which maps to the Berkeley UNIX sockets servent structure.
name Official name of the service
aliasList aliases Array of aliases for the service name.
protoName Name of the protocol to use.
reserved Reserved for future use.

NetServInfoType

The NetServInfoType structure maps to the servent structure in Berkeley UNIX sockets API. It contains information about a service.

struct {
    Char * nameP;
    Char ** nameAliasesP;
    UInt16 port;
    Char * protoP;
} NetServInfoType, *NetServInfoPtr;

Field Descriptions

nameP Official name of the service
nameAliasesP Array of aliases for the service name.
port Port number for the service.
protoP Name of the protocol to use.

NetSocketAddrEnum

The NetSocketAddrEnum enum specifies the address types supported by the net library.

typedef enum {
    netSocketAddrRaw = 0,
    netSocketAddrINET = 2
} NetSocketAddrEnum

Value Descriptions

netSocketAddrRaw Raw address. Supported in Palm OS® version 3.0 and higher.
netSocketAddrINET IP address.

NetSocketAddrINType

The NetSocketAddrINType struct holds an internet socket address, that is, a socket that uses one of the internet protocols. This structure directly maps to the BSD UNIX sockaddr_in structure.

typedef struct NetSocketAddrINType {
    Int16 family;
    UInt16 port;
    NetIPAddr addr;
} NetSocketAddrINType;

Field Descriptions

family Address family in host byte order. This is either netSocketAddrINET or netSocketAddrRaw.
port The port in network byte order.
addr The IP address in network byte order.

NetSocketAddrRawType

The NetSocketAddrRawType structure holds a raw socket address.

typedef struct NetSocketAddrRawType {
    Int16 family;
    UInt16 ifInstance;
    UInt32 ifCreator;
} NetSocketAddrRawType;

Field Descriptions

family Address family in host byte order. This is either netSocketAddrINET or netSocketAddrRaw.
ifInstance The instance number of the interface that the socket uses to send and receive data.
ifCreator The creator of the interface that the socket uses.

Compatibility

Raw sockets are supported in Palm OS® version 3.0 and higher.

NetSocketAddrType

The NetSocketAddrType structure holds a generic socket address. This struct can hold any type of address including Internet addresses. It directly maps to the BSD UNIX sockaddr structure.

Note that this structure is the same size as NetSocketAddrINType and NetSocketAddrRawType. This means that one of those two structures can be used for parameters declared to be NetSocketAddrType.

typedef struct NetSocketAddrType {
    Int16 family;
    UInt8 data[14];
} NetSocketAddrType;

NetSocketRef

The NetSocketRef defines a socket descriptor. The socket descriptor is created and returned by NetLibSocketOpen. It is used in any function that requires access to a socket.

typedef Int16 NetSocketRef

NetSocketTypeEnum

The NetSocketTypeEnum enum specifies the available socket types.

typedef enum {
    netSocketTypeStream=1,
    netSocketTypeDatagram=2,
    netSocketTypeRaw=3,
    netSocketTypeReliableMsg=4
} NetSocketTypeEnum

Value Descriptions

netSocketTypeStream Streams protocol over wireline.
netSocketTypeDatagram UDP protocol.
netSocketTypeRaw Raw mode.

Net Library Constants

I/O Flags

The I/O flags specify special handling instructions to functions that send and receive data. You can OR these values together to specify more than one.

netIOFlagOutOfBand Process out-of-band data. Available for send calls only.
netIOFlagPeek Peek at incoming message without dequeuing it.
netIOFlagDontRoute Send without using routing. This constant is currently ignored.

Tracing Bits

The tracing bits are used to set the level of event tracing. An application can get a list of events in the trace buffer using the NetLibMaster call.

You can set the tracing for each network interface using NetLibIFSettingSet and for the net library in general with NetLibSettingSet.

netTracingErrors Record run-time errors. This is the default.
netTracingMsgs Record application trace messages.
netTracingPkts Record packets I/O.
netTracingFuncs Record function flow.
netTracingAppMsgs Record application messages sent using NetLibTracePrintF and NetLibTracePutS.

Net Library Functions




NetHToNL

Purpose

Macro that converts a 32-bit value from host to network byte order.

Prototype

NetHToNL (x)

Parameters

  -> x
 32-bit value to convert.

Result

Returns x in network byte order.

Sockets Equivalent

htonl()

See Also

NetNToHS, NetNToHL, NetHToNS



NetHToNS

Purpose

Macro that converts a 16-bit value from host to network byte order.

Prototype

NetHToNS (x)

Parameters

  -> x
 16-bit value to convert.

Result

Returns x in network byte order.

Sockets Equivalent

htons()

See Also

NetNToHS, NetNToHL, NetHToNL



NetLibAddrAToIN

Purpose

Converts an ASCII string representing a dotted decimal IP address into a 32-bit IP address in network byte order.

Prototype

NetIPAddr NetLibAddrAToIN (UInt16 libRefnum, Char *a)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> a
 Pointer to ASCII dotted decimal string.

Result

Returns a 32-bit network byte order IP address or -1 if a doesn't represent a dotted decimal IP address

Sockets Equivalent

UInt32 inet_addr(char* cp)

See Also

NetLibAddrINToA



NetLibAddrINToA

Purpose

Converts an IP address from 32-bit network byte order into a dotted decimal ASCII string.

Prototype

Char * NetLibAddrINToA (UInt16 libRefnum, NetIPAddr inet, Char *spaceP)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> inet
 32-bit IP address in network byte order.
  <- spaceP
 Buffer used to hold the return value.

Result

Returns in spaceP the dotted decimal ASCII string representation of the IP address.

Sockets Equivalent

char* inet_ntoa(struct in_addr in)

See Also

NetLibAddrAToIN



NetLibClose

Purpose

Closes the net library.

Prototype

Err NetLibClose (UInt16 libRefnum, UInt16 immediate)

Parameters

  -> libRefnum
 Reference number of the net library.
  -> immediate
 If true, library will shut down immediately. If false, library will shut down only if close timer expires before another NetLibOpen is issued.

Result

Returns one of the following values:
  0
 Success.
  netErrNotOpen
 Library was not open.
  netErrStillOpen
 Not really an error; returned if library is still in use by another application.

Sockets Equivalent

None.

Comments

Applications must call this function when they no longer need the net library. If the net library open count is greater than 1 before this call is made, the count is decremented and netErrStillOpen is returned. If the open count was 1, the library takes the following action:

  • If immediate is true, the library shuts down immediately. All network interfaces are brought down, the net protocol stack task is terminated, and all memory used by the net library is freed.

  • If immediate is false, a close timer is created and this call returns immediately without actually bringing the net library down. Instead it leaves it up and running but marks it as in the "close-wait" state. It remains in this state until either the timer expires or another NetLibOpen is issued. If the timer expires, the library is shut down. If another NetLibOpen call is issued before the timer expires (possibly by another application), the timer is cancelled and the library is marked as fully open.

In most cases, you should pass false for immediate. This allows the user to quit one Internet application and launch another within a short period of time without having to wait through the process of closing down and then re-establishing dial-up network connections.

See Also

NetLibOpen, NetLibOpenCount



NetLibConnectionRefresh

Purpose

This routine is a convenience call for applications. It checks the status of all connections and optionally tries to open any that were closed.

Prototype

Err NetLibConnectionRefresh (UInt16 refNum, Boolean refresh, UInt8 *allInterfacesUpP, UInt16 * netIFErrP)

Parameters

  -> refnum
 Reference number of the net library.
  -> refresh
 If true, any connections that aren't currently open are opened.
  <- allInterfacesUpP
 Set to true if all connections are open.
  <- netIFErrP
 First error encountered when reopening connections that were closed. (See NetLibIFUp for a list of possible values.)

Result

 

  0
 Success.

netErrBufTooSmall

netErrOutOfCmdBlocks

netErrNoInterfaces

Sockets Equivalent

None.

Comments

This function determines whether a connection is up based on the internal status of the TCP/IP stack. To test the presence of a "physical connection" (phone line, modem, serial cable), a command should be sent once it's been determined that the logical connection is up. If the physical connection is broken, nothing returns and a timeout error eventually occurs.



NetLibDmReceive

Purpose

Receive data from a socket directly into a database record.

Prototype

Int16 NetLibDmReceive (UInt16 libRefNum, NetSocketRef socket, void* recordP, UInt32 recordOffset, UInt16 rcvLen, UInt16 flags, void* fromAddrP, UInt16 *fromLenP, Int32 timeout, Err* errP)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> socket
 Descriptor for the open socket.
  <- recordP
 Pointer to beginning of record to receive data into. Must be locked for use.
  -> recordOffset
 Offset from beginning of record to read data into.
  -> rcvLen
 Maximum number of bytes to read.
  -> flags
 One or more netIOFlagxxx flags. See "I/O Flags."
  <- fromAddrP
 Pointer to buffer to hold address of sender (a NetSocketAddrType struct). Pass NULL if you don't need sender information.
  <-> fromLenP
 On entry, size of fromAddrP buffer. On exit, actual size of returned address in fromAddrP. Pass NULL if you don't need sender information.
  -> timeout
 Maximum timeout in system ticks; -1 means wait forever.
  <- errP
 Contains an error code if the return value is -1.

Result

Returns the number of bytes successfully received. If the return value is 0, the socket has been shut down by the remote host. If the return value is -1, an error has occurred and errP contains one of the following values:
  0
 No error.
  netErrTimeout
 Call timed out.
  netErrNotOpen
 The referenced net library has not been opened yet.

netErrParamErr

netErrSocketNotOpen

netErrWouldBlock

netErrUserCancel

netErrOutOfMemory

Comments

This call behaves similarly to NetLibReceive but reads the data directly into a database record, which is normally write-protected. The caller must pass a pointer to the start of the record and an offset into the record of where to start the read.



NetLibFinishCloseWait

Purpose

Forces the net library to do a complete close if it's currently in the close-wait state.

Prototype

Err NetLibFinishCloseWait (UInt16 libRefnum)

Parameters

  -> libRefnum
 Reference number of the net library.

Result

 

  0
 Success.

netErrTimeout

Sockets Equivalent

None.

Comments

This call checks the current open state of the net library. If it's in the close-wait state (see NetLibClose), it forces the library to perform an immediate, complete close operation.



NetLibGetHostByAddr

Purpose

Looks up a host name given its IP address.

Prototype

NetHostInfoPtr NetLibGetHostByAddr (UInt16 libRefnum, UInt8 *addrP, UInt16 len, UInt16 type, NetHostInfoBufPtr bufP, Int32 timeout, Err *errP)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> addrP
 IP address of host to lookup.
  -> len
 Length, in bytes, of *addrP.
  -> type
 Type of addrP. See NetSocketAddrEnum.
  <- bufP
 Pointer to a NetHostInfoBufType struct in which to store the results of the lookup.
  -> timeout
 Maximum timeout in system ticks; -1 means wait forever.
  <- errP
 Contains an error code if the return value is 0.

Result

Returns a pointer to the NetHostInfoType portion of bufP that contains results of the lookup. If the return value is 0, an error has occurred, and errP contains one of the following values:
  0
 No error
  netErrTimeout
 Call timed out.
  netErrNotOpen
 The referenced net library has not been opened yet.

netErrDNSNameTooLong

netErrDNSBadName

netErrDNSLabelTooLong

netErrDNSAllocationFailure

netErrDNSTimeout

netErrDNSUnreachable

netErrDNSFormat

netErrDNSServerFailure

netErrDNSNonexistantName

netErrDNSNIY

netErrDNSRefused

netErrDNSImpossible

netErrDNSNoRRS

netErrDNSAborted

netErrDNSBadProtocol

netErrDNSTruncated

netErrDNSNoRecursion

netErrDNSIrrelevant

netErrDNSNotInLocalCache

netErrDNSNoPort

Sockets Equivalent

struct hostent* gethostbyaddr (char* addr, int len, int type);

Comments

This call queries the domain name server(s) to look up a host name given its IP address.

See Also

NetLibGetHostByName



NetLibGetHostByName

Purpose

Looks up a host IP address given a host name.

Prototype

NetHostInfoPtr NetLibGetHostByName (UInt16 libRefnum, Char *nameP, NetHostInfoBufPtr bufP, Int32 timeout, Err *errP)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> nameP
 Name of host to look up.
  <- bufP
 Pointer to a NetHostInfoBufType struct in which to store the results of the lookup.
  -> timeout
 Maximum timeout in system ticks; -1 means wait forever.
  <- errP
 Contains an error code if the return value is 0.

Result

Returns a pointer to the NetHostInfoType portion of bufP, which contains results of the lookup. If the return value is 0, an error has occurred and errP contains one of the following values:
  0
 No error
  netErrTimeout
 Call timed out.
  netErrNotOpen
 The referenced net library has not been opened yet.

netErrDNSNameTooLong

netErrDNSBadName

netErrDNSLabelTooLong

netErrDNSAllocationFailure

netErrDNSTimeout

netErrDNSUnreachable

netErrDNSFormat

netErrDNSServerFailure

netErrDNSNonexistantName

netErrDNSNIY

netErrDNSRefused

netErrDNSImpossible

netErrDNSNoRRS

netErrDNSAborted

netErrDNSBadProtocol

netErrDNSTruncated

netErrDNSNoRecursion

netErrDNSIrrelevant

netErrDNSNotInLocalCache

netErrDNSNoPort

Sockets Equivalent

struct hostent *gethostbyname(char* name);

Comments

This call first checks the local name -> IP address host table in the net library preferences. If the entry is not found, it then queries the domain name server(s).

See Also

NetLibGetHostByAddr, NetLibGetMailExchangeByName



NetLibGetMailExchangeByName

Purpose

Looks up the name of a host to use for a given mail exchange.

Prototype

Int16 NetLibGetMailExchangeByName (UInt16 libRefNum, Char *mailNameP, UInt16 maxEntries, Char hostNames[][netDNSMaxDomainName+1], UInt16 priorities[], Int32 timeout, Err* errP)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> mailNameP
 Name of the mail exchange to look up.
  -> maxEntries
 Maximum number of host names to return.
  <- hostNames
 Array of character strings of length netDNSMaxDomainName+1. The host name results are stored in this array. This array must be able to hold at least maxEntries host names.
  <- priorities
 Array of Words. The priorities of each host name found are stored in this array. This array must be at least maxEntries in length.
  -> timeout
 Maximum timeout in system ticks; -1 means wait forever.
  <- errP
 Contains an error code if the return value is less than 0.

Result

Returns the number of entries successfully found. If the return value is a negative number, an error has occurred, and errP contains one of the following values:
  0
 No error
  netErrTimeout
 Call timed out.
  netErrNotOpen
 The referenced net library has not been opened yet.

netErrDNSNameTooLong

netErrDNSBadName

netErrDNSLabelTooLong

netErrDNSAllocationFailure

netErrDNSTimeout

netErrDNSUnreachable

netErrDNSFormat

netErrDNSServerFailure

netErrDNSNonexistantName

netErrDNSNIY

netErrDNSRefused

netErrDNSImpossible

netErrDNSNoRRS

netErrDNSAborted

netErrDNSBadProtocol

netErrDNSTruncated

netErrDNSNoRecursion

netErrDNSIrrelevant

netErrDNSNotInLocalCache

netErrDNSNoPort

Sockets Equivalent

None

Comments

This call looks up the name(s) of host(s) to use for sending an e-mail. The caller passes the name of the mail exchange in mailNameP and gets back a list of host names to which the mail message can be sent.

See Also

NetLibGetHostByAddr, NetLibGetHostByName



NetLibGetServByName

Purpose

Looks up the port number for a standard TCP/IP service, given the desired protocol.

Prototype

NetServInfoPtr NetLibGetServByName (UInt16 libRefnum, const Char *servNameP, const Char *protoNameP, NetServInfoBufPtr bufP, Int32 timeout, Err* errP)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> servNameP
 Name of the service to look up. Possible services are "echo", "discard", "daytime", "qotd", "chargen", "ftp-data", "ftp", "telnet", "smtp", "time", "name", "finger", "pop2", "pop3", "nntp", "imap2".
  -> protoNameP
 Desired protocol to use, either "udp" or "tcp".
  <- bufP
 Pointer to a NetServInfoBufType struct in which to store the results of the lookup.
  -> timeout
 Maximum timeout in system ticks; -1 means wait forever.
  <- errP
 Contains an error code if the return value is 0.

Result

Returns a pointer to the NetServInfoType portion of bufP that contains results of the lookup. If the return value is 0, and error has occurred and errP contains one of the following values:
  0
 No error
  netErrTimeout
 Call timed out.
  netErrNotOpen
 The referenced net library has not been opened yet.

netErrUnknownProtocol

netErrUnknownService

Sockets Equivalent

struct servent* getservbyname(char* addr, char* proto);

Comments

This call is a convenience call for looking up a standard port number given the name of a service and the protocol to use.

See Also

NetLibGetHostByName



NetLibIFAttach

Purpose

Attach a new network interface.

Prototype

Err NetLibIFAttach (UInt16 libRefnum, UInt32 ifCreator, UInt16 ifInstance, Int32 timeout)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> ifCreator
 Creator of interface to attach.
  -> ifInstance
 Instance number of interface to attach. The instance number is one of the values returned by NetLibIFGet.
  -> timeout
 Timeout in ticks; -1 means infinite timeout.

Result

Returns one of the following values:
  0
 Success.

netErrInterfaceNotFound

netErrTooManyInterfaces

Sockets Equivalent

None

Comments

This call can be used to attach a new network interface to the net library. Network interfaces are self-contained databases of type 'neti'. The ifCreator parameter to this function is used to locate the network interface database of the given creator.

If the net library is already open when this call is made, the network interface's database will be located and then called to initialize itself and attach itself to the protocol stack in real time. If the net library is not open when this call is made, the creator and instance number of the interface are stored in the net library's preferences database and the interface is initialized and attached to the stack the next time the net library is opened.

See Also

NetLibIFGet, NetLibIFDetach



NetLibIFDetach

Purpose

Detach a network interface from the protocol stack.

Prototype

Err NetLibIFDetach (UInt16 libRefnum, UInt32 ifCreator, UInt16 ifInstance, Int32 timeout)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> ifCreator
 Creator of interface to detach.
  -> ifInstance
 Instance number of interface to detach.
  -> timeout
 Timeout in ticks; -1 means infinite timeout.

Result

Returns one of the following values:
  0
 Success.

netErrInterfaceNotFound

Sockets Equivalent

None

Comments

If the net library is already open when this call is made, the interface is brought down and detached from the protocol stack in real time. If the net library is not open when this call is made, the creator and instance number of the interface are removed in the net library's preferences database and the interface is not attached the next time the library is opened.

See Also

NetLibIFGet, NetLibIFAttach



NetLibIFDown

Purpose

Bring an interface down and hang up a connection.

Prototype

Err NetLibIFDown (UInt16 libRefnum, UInt32 ifCreator, UInt16 ifInstance, Int32 timeout)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> ifCreator
 Creator of interface to attach.
  -> ifInstance
 Instance number of interface to attach.
  -> timeout
 Timeout in ticks; -1 means wait forever.

Result

Returns one of the following values:
  0
 Success.
  netErrNotOpen
 The referenced net library has not been opened yet.

netErrInterfaceNotFound

Sockets Equivalent

None

Comments

The net library must be open before this call can be made. For dial-up interfaces, this call terminates a connection and hangs up the modem if necessary.

NetLibClose automatically brings down any attached interfaces, so this routine doesn't normally have to be called.

If the interface is already down, this routine returns immediately with no error.

See Also

NetLibIFGet, NetLibIFAttach, NetLibIFDetach, NetLibIFUp



NetLibIFGet

Purpose

Get the creator and instance number of an installed interface by index.

Prototype

Err NetLibIFGet (UInt16 libRefnum, UInt16 index, UInt16 * ifCreatorP, UInt16 * ifInstanceP)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> index
 Index of the interface to get. Indices start at 0.
  <- ifCreatorP
 The interface's creator.
  <- ifInstanceP
 The interface's instance number.

Result

Returns one of the following values:
  0
 Success.
  netErrInvalidInterface
 Index too high
  netErrPrefNotFound
 No current value for setting.

Sockets Equivalent

None

Comments

To get a list of all installed interfaces, call this function with successively increasing indices starting from 0 until the error netErrInvalidInterface is returned.

The ifCreator and ifInstance values returned from this call can then be used with the NetLibSettingGet call to get more information about that particular interface.

See Also

NetLibIFAttach, NetLibIFDetach, "Settings for Interface Selection" in the Palm OS Programmer's Companion



NetLibIFSettingGet

Purpose

Retrieves a network interface specific setting.

Prototype

Err NetLibIFSettingGet (UInt16 libRefnum, UInt32 ifCreator, UInt16 ifInstance, UInt16 setting, void *valueP, UInt16 *valueLenP)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> ifCreator
 Creator of the network interface.
  -> ifInstance
 Instance number of the network interface.
  -> setting
 Setting to retrieve; one of the NetIFSettingEnum constants.
  <- valueP
 Space for return value of setting.
  <-> valueLenP
 On entry, size of valueP. On exit, actual size of setting.

Result

Returns one of the following values:
  0
 Success.
  netErrUnknownSetting
 Invalid setting constant.
  netErrPrefNotFound
 No current value for setting.
  netErrBufTooSmall
 valueP was too small to hold entire setting. Setting value was truncated to fit in valueP.

netErrUnimplemented

netErrInterfaceNotFound

netErrBufWrongSize

Sockets Equivalent

None

Comments

This call can be used to retrieve the current value of any network interface setting. The caller must pass a pointer to a buffer to hold the return value (valueP), the size of the buffer (*valueLenP), and the setting ID (setting). The setting ID is one of the constants in the NetIFSettingEnum type.

Some settings, such as the login script, are variable size. For these types of settings, you can obtain the actual size required for the buffer by passing 0 for *valueLenP. The required size is returned in valueLenP.

Table 54.1 lists the network interface settings and the size of each setting. Some are only applicable to certain types of interfaces. Settings not applicable to a specific interface can be safely ignored and not set to any particular value.

Table 54.1 Network Interface Settings 
netIFSetting... Type Description
ResetAll void Use with NetLibIFSettingSet only. This clears all other settings for the interface to their default values.
Up UInt8 Read-only. true if interface is currently up.
Name Char[32] Read-only. Name of this interface.
ReqIPAddr UInt32 IP address of interface.
SubnetMask UInt32 Subnet mask for interface. Doesn't need to be specified for PPP or SLIP type connections.
Broadcast UInt32 Broadcast address for interface. Doesn't need to be specified for PPP or SLIP type connections.
Username Char[32] User name. Only required if the login script uses the user name substitution escape sequence in it. Call NetLibIFSettingSet with a valueLen of 0 to remove this setting.
Password Char[32] Password. Only required if the login script uses the password substitution escape sequence in it. Call NetLibIFSettingSet with a valueLen of 0 to remove this setting. If the login script uses password substitution and no password setting is set, the user will be prompted for a password at connect time.
AuthUsername Char[32] Authentication user name. Only required if the authentication protocol uses a different user name than the what's in the netIFSettingUsername setting. If this setting is empty (valueLen of 0), the Username setting will be used instead. Call NetLibIFSettingSet with a valueLen of 0 to remove this setting.
AuthPassword Char[32] Authentication password. If "$" then the user will be prompted for the authentication password at connect time. Else, if 0 length, then the netIFSettingPassword setting or the result of its prompt will be used instead. Call NetLibIFSettingSet with a valueLen of 0 to remove this setting.
ServiceName Char[] Service name. Used for display purposes while showing the connection progress dialog box. Call NetLibIFSettingSet with a valueLen of 0 to remove this setting.
LoginScript Char[] Login script. Only required if the particular service requires a login sequence. Call NetLibIFSettingSet with a valueLen of 0 to remove this setting. See below for a description of the login script format.
ConnectLog Char[] Connect log. Generally, this setting is just retrieved, not set. It contains a log of events from the most recent login. To clear this setting, call NetLibIFSettingSet with a valueLen of 0.
InactivityTimeout UInt16 Maximum number of seconds of inactivity allowed. Set to 0 to ignore.
EstablishmentTimeout UInt16 Maximum delay, in seconds, allowed between each stage of connection establishment or login script line. Must be non-zero.
DynamicIP UInt8 If non-zero, negotiate for an IP address. If false, the IP address specified in the netIFSettingReqIPAddr setting will be used. Default is false.
VJCompEnable UInt8 If non-zero, enable VJ header compression. Default is true for PPP, false for SLIP, and true for CSLIP.
VJCompSlots UInt8 Number of slots to use for VJ compression. Default is 4 for PPP and 16 for SLIP and CSLIP. More slots require more memory so it is best to keep this number to a minimum.
MTU UInt16 Maximum transmission unit in octets. Currently not implemented in SLIP or PPP.
AsyncCtlMap UInt32 Bit mask of characters to escape for PPP. Default is 0.
PortNum UInt16 Which serial communication port to use. Port 0 is the only port available on the device.
BaudRate UInt32 Serial port baud rate to use in bits per second.
FlowControl UInt8 If bit 0 is 1, use hardware handshaking on the serial port. Default is no hardware handshaking.
StopBits UInt8 Number of stop bits. Default is 1.
ParityOn UInt8 true if parity detection enabled. Default is false.
ParityEven UInt8 true for even parity detection. Default is true.
UseModem UInt8 If true, dial-up through modem. If false, go direct over serial port
PulseDial UInt8 If true, pulse dial modem. Else, tone dial. Default is tone dial.
ModemInit Char[] Zero-terminated modem initialization string, not including the "AT". If not specified (valueLen of 0), the modem initialization string from system preferences are used.
ModemPhone Char[] Zero-terminated modem phone number string. Only required if netIFSettingUseModem is true.
RedialCount UInt16 Number of times to redial modem when trying to establish a connection. Only required if netIFSettingUseModem is true.
DNSQuery UInt8 true if PPP queries for DNS address. The default is true.
TraceBits UInt32 A bitfield of various trace bits. See "Tracing Bits."

An application can get a list of events in the trace buffer using the NetLibMaster call. Each interface has its own trace bits setting so that trace event recording in each interface can be selectively enabled or disabled.
ActualIPAddr UInt32 Read-only. The actual IP address that the interface ends up using. The login script execution engine stores the result of the "g" (get IP address) command here as does the PPP negotiation logic.
ServerIPAddr UInt32 Read-only. The IP address of the PPP server we're connected to.
BringDownOnPowerDown UInt8 true if the interface is brought down when the Palm OS® device is turned off.
RawMode UInt32 Specifies if the interface is in raw mode. The net library places an interface in raw mode when it is bound to a raw socket in the raw domain. Raw sockets are available in Palm OS version 3.0 and higher.

See Also

NetLibIFSettingSet, NetLibSettingGet, NetLibSettingSet, "Interface Specific Settings" in the Palm OS Programmer's Companion



NetLibIFSettingSet

Purpose

Sets a network interface specific setting.

Prototype

Err NetLibIFSettingSet (UInt16 libRefnum, UInt32 ifCreator, UInt16 ifInstance, UInt16 setting, void* valueP, UInt16 valueLen)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> ifCreator
 Creator of the network interface.
  -> ifInstance
 Instance number of the network interface.
  -> setting
 The setting to set, one of the NetIFSettingEnum constants. See Table 54.1.
  -> valueP
 Space new value of setting.
  -> valueLen
 Size of new setting.

Result

Returns one of the following values:
  0
 Success.
  netErrUnknownSetting
 Invalid setting constant.
  netErrPrefNotFound
 No current value for setting.
  netErrBufTooSmall
 valueP was too small to hold entire setting. Setting value was truncated to fit in valueP.

netErrUnimplemented

netErrInterfaceNotFound

netErrBufWrongSize

netErrReadOnlySetting

Sockets Equivalent

None

Comments

This call can be used to set the current value of any network interface setting. The caller must pass a pointer to a buffer which holds the new value (valueP), the size of the buffer (valueLen), and the setting ID (setting).

See NetLibIFSettingGet for an explanation of each of the settings.

Of particular interest is the netIFSettingResetAll setting, which, if used, resets all settings for the interface to their default values. When using this setting, valueP and valueLen are ignored.

See Also

NetLibIFSettingGet, NetLibSettingGet, NetLibSettingSet, "Interface Specific Settings" in the Palm OS Programmer's Companion



NetLibIFUp

Purpose

Bring an interface up and establish a connection.

Prototype

Err NetLibIFUp (UInt16 libRefnum, UInt32 ifCreator, UInt16 ifInstance)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> ifCreator
 Creator of interface to attach.
  -> ifInstance
 Instance number of interface to attach.

Result

Returns one of the following values:
  0
 Success.
  netErrNotOpen
 The referenced net library has not been opened yet.

netErrInterfaceNotFound

netErrUserCancel

netErrBadScript

netErrPPPTimeout

netErrAuthFailure

netErrPPPAddressRefused

Sockets Equivalent

None

Comments

The net library must be open before this call can be made. For dial-up interfaces, this call will dial up the modem if necessary and run through the connect script to establish the connection.

If the interface is already up, this routine returns immediately with no error. This call doesn't take a timeout parameter because it relies on each interface to have its own established timeout setting.

See Also

NetLibIFGet, NetLibIFAttach, NetLibIFDetach, NetLibIFDown



NetLibMaster

Purpose

Retrieves the network statistics, interface statistics, and the contents of the trace buffer.

Prototype

Err NetLibMaster (UInt16 libRefnum, UInt16 cmd, NetMasterPBPtr pbP, Int32 timeout) 

Parameters

  -> libRefNum
 Reference number of the net library.
  -> cmd
 Function to perform (NetMasterEnum type). The following commands are supported:
  netMasterInterfaceInfonetMasterInterfaceStatsnetMasterIPStatsnetMasterICMPStatsnetMasterUDPStatsnetMasterTCPStats
 netMasterInterfaceInfonetMasterInterfaceStatsnetMasterIPStatsnetMasterICMPStatsnetMasterUDPStatsnetMasterTCPStatsnetMasterTraceEventGet
  <-> pbP
 Command parameter block.
  -> timeout
 Timeout in ticks; -1 means wait forever.

Result

Returns one of the following values:
  0
 No error
  netErrNotOpen
 The referenced net library has not been opened yet.

netErrParamErr

netErrUnimplemented

Sockets Equivalent

None

Comments

This call allows applications to get detailed information about the net library. This information is usually helpful in debugging network configuration problems.

This function takes a command word (cmd) and parameter block pointer (pbP) as arguments and returns its results in the parameter block on exit. Which values you must specify in the parameter block and which values are returned are specific to the command you specify.

netMasterInterfaceInfo

The pbP->interfaceInfo struct specifies interface information.

-> index Index of interface to fetch info about.
<- creator Creator of interface.
<- instance Instance of interface.
<- netIFP Private interface info pointer.
<- drvrName Driver type that interface uses ("PPP", "SLIP", etc.).
<- hwName Hardware driver name ("Serial Library", etc.).
<- localNetHdrLen Number of bytes in local net header.
<- localNetTrailerLen Number of bytes in local net trailer.
<- localNetMaxFrame Local net maximum frame size.
<- ifName Interface name with instance number concatenated.
<- driverUp true if interface driver is up.
<- ifUp true if interface media layer is up.
<- hwAddrLen Length of interface's hardware address.
<- hwAddr Interface's hardware address.
<- mtu Maximum transfer unit of interface.
<- speed Speed in bits per second.
<- lastStateChange Time in milliseconds of last state change.
<- ipAddr IP address of interface.
<- subnetMask Subnet mask of local network.
<- broadcast Broadcast address of local network.

netMasterInterfaceStats

The pbP->interfaceStats structure specifies interface statistics.

-> index Index of interface to fetch info about.
<- inOctets Number of octets received.
<- inUcastPkts Number of packets received.
<- inNUcastPkts Number of broadcast packets received.
<- inDiscards Number of incoming packets that were discarded.
<- inErrors Number of packet errors encountered.
<- inUnknownProtos Number of unknown protocols encountered.
<- outOctets Number octets sent.
<- outUcastPkts Number of packets sent.
<- outNUcastPkts Number of broadcast packets sent.
<- outDiscards Number of packets discarded.
<- outErrors Number of outbound packet errors.

netMasterIPStats

The pbP->ipStats structure contains statistics about the IP protocol. See NetMgr.h for a complete list of statistics returned.

netMasterICMPStats

The pbP->icmpStats structure contains statistics about the ICMP protocol. See NetMgr.h for a complete list of statistics returned.

netMasterUDPStats

The pbP->udpStats structure contains statistics about the UDP protocol. See NetMgr.h for a complete list of statistics returned.

netMasterTCPStats

The pbP->tcpStats structure contains statistics about the TCP protocol. See NetMgr.h for a complete list of statistics returned.

netMasterTraceEventGet

The pbP->traceEventGet structure contains a trace event.

-> index Index of event to fetch.
<- textP Pointer to text string to return event in. Should be at least 256 bytes long.

See Also

NetLibSettingSet



NetLibOpen

Purpose

Opens and initializes the net library.

Prototype

Err NetLibOpen (UInt16 libRefnum, UInt16 *netIFErrP)

Parameters

  -> libRefnum
 Reference number of the net library.
  <- netIFErrP
 First error encountered when bringing up network interfaces. (See NetLibIFUp for a list of possible values.)

Result

Returns one of the following values:
  0
 No error.
  netErrAlreadyOpen
 Not really an error; returned if library was already open and the open count was simply incremented.
  netErrOutOfMemory
 Not enough memory available to open the library.
  netErrNoInterfaces
 Incorrect setup.
  netErrPrefNotFound
 Incorrect setup.

Comments

Applications must call this function before using the net library. If the net library was already open, NetLibOpen increments its open count. Otherwise, it opens the library, initializes it, starts up the net protocol stack component of the library as a separate task, and brings up all attached network interfaces.

NetLibOpen uses settings saved in the net library's preferences database during initialization. These settings include the interfaces to attach, the IP addresses, etc. It's assumed that these settings have been previously set up by a preference panel or equivalent so an application doesn't normally have to set them up before calling NetLibOpen.

If any of the attached interfaces fails to come up, *netIFErrP will contain the error number of the first interface that encountered a problem.

See Also

SysLibFind, NetLibClose, NetLibOpenCount



NetLibOpenCount

Purpose

Retrieves the open count of the net library.

Prototype

Err NetLibOpenCount (UInt16 libRefnum, UInt16 *countP)

Parameters

  -> libRefnum
 Reference number of the net library.
  <- countP
 Contains the open count of the net library upon return.

Result

 

Sockets Equivalent

None.

Comments

This call will most likely only be used by the Network preferences panel. Most applications will simply call NetLibOpen unconditionally during startup and NetLibClose when they exit.



NetLibReceive

Purpose

Receive data from a socket into a single buffer.

Prototype

Int16 NetLibReceive (UInt16 libRefNum, NetSocketRef socket, void* bufP, UInt16 bufLen, UInt16 flags, void* fromAddrP, UInt16 * fromLenP, Int32 timeout, Err* errP);

Parameters

  -> libRefNum
 Reference number of the net library.
  -> socket
 Descriptor for the open socket.
  <- bufP
 Pointer to buffer to hold received data.
  -> bufLen
 Length of bufP buffer.
  -> flags
 One or more netIOFlagxxx flags. See "I/O Flags."
  <- fromAddrP
 Pointer to buffer to hold address of sender (a NetSocketAddrType).
  <-> fromLenP
 On entry, size of fromAddrP buffer. On exit, actual size of returned address in fromAddrP.
  -> timeout
 Maximum timeout in system ticks; -1 means wait forever.
  <- errP
 Contains an error code if the return value is -1.

Result

Returns the number of bytes successfully received. If the return value is 0, the socket has been shut down by the remote host. If the return value is -1, an error has occurred, and errP contains one of the following values:
  0
 No error.
  netErrTimeout
 Call timed out.
  netErrNotOpen
 The referenced net library has not been opened yet.

netErrParamErr

netErrSocketNotOpen

netErrWouldBlock

netErrUserCancel

Sockets Equivalent

int recvfrom (int socket, const void* bufP, int bufLen, int flags, const void* fromAddrP, int* fromLenP);

int recv(int socket, const void* bufP, int bufLen, int flags);

int read(int socket, const void* bufP, int bufLen);

Comments

For stream-based sockets, this call reads whatever bytes are available and returns the number of bytes actually read into the caller's buffer. If there is no data available, this call will block until at least one byte arrives, until the socket is shut down by the remote host, or until a timeout occurs.

For datagram-based sockets, this call reads a complete datagram and returns the number of bytes in the datagram. If the caller's buffer is not large enough to hold the entire datagram, the end of the datagram is discarded. If a datagram is not available, this call will block until one arrives, or until the call times out.

The data is read into a single buffer pointed to by bufP.

See Also

NetLibReceive, NetLibDmReceive, NetUReadN, NetLibSend, NetLibSendPB



NetLibReceivePB

Purpose

Receive data from a socket into a multi-buffer gather-read array.

Prototype

Int16 NetLibReceivePB (UInt16 libRefnum, NetSocketRef socket, NetIOParamType* pbP, UInt16 flags, Int32 timeout, Err* errP)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> socket
 Descriptor for the open socket.
  -> pbP
 Pointer to parameter block containing buffer info.
  -> flags
 One or more netIOFlagxxx flags. See "I/O Flags."
  -> timeout
 Maximum timeout in system ticks; -1 means wait forever.
  <- errP
 Contains an error code if the return value is -1.

Result

Returns the number of bytes successfully received. Returns 0 if the socket has been shut down by the remote host. If the return value is -1, an error has occurred, and errP contains one of the following values:
  0
 No error.
  netErrTimeout
 Call timed out.
  netErrNotOpen
 The referenced net library has not been opened yet.

netErrParamErr

netErrSocketNotOpen

netErrWouldBlock

Sockets Equivalent

int recvmsg (int socket, const struct msghdr* pbP, int flags);

Comments

The pbP parameter is a pointer to a NetIOParamType structure. NetIOParamType is defined as follows:

typedef struct {
    UInt8 * addrP;
    UInt16 addrLen;
    NetIOVecPtr iov;
    UInt16 iovLen;
    UInt8 * accessRights;
    UInt16 accessRightsLen;
} NetIOParamType, *NetIOParamPtr;

You provide the following information in this struct:

addrP Address of sender, set by NetLibReceivePB. Set to 0 if you don't require this field.
addrLen Length of *addrP.
iov Array of buffers into which the data should be received. NetIOVecPtr is a pointer to a NetIOVecType structure, which has two fields:
  bufP
 Pointer to a buffer.
  bufLen
 Length of bufP.
iovLen Length of the iov array.
accessRights Access rights. This field currently isn't used and should be set to 0.
accessRightsLen Length of the *accessRights. This field currently isn't used and should be set to 0.

For stream-based sockets, this call reads whatever bytes are available and returns the number of bytes actually read into the caller's buffer. If no data is available, this call will block until at least one byte arrives, until the socket is shut down by the remote host, or until a timeout occurs.

For datagram-based sockets, this call reads a complete datagram and returns the number of bytes in the datagram. If the caller's buffer is not large enough to hold the entire datagram, the end of the datagram is discarded. If a datagram is not available, this call will block until one arrives, or until the call times out.

The data is read into the gather-read array specified by the pbP->iov array.

See Also

NetLibReceive, NetLibDmReceive, NetLibSend, NetLibSendPB



NetLibSelect

Purpose

Blocks until I/O is ready on one or more descriptors, where a descriptor can represent socket input, socket output, or a user input event like a pen tap or key press.

Prototype

Int16 NetLibSelect (UInt16 libRefnum, UInt16 width, NetFDSetType* readFDs, NetFDSetType* writeFDs, NetFDSetType* exceptFDs, Int32 timeout, Err* errP)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> width
 Number of descriptor bits to check in the readFDs, writeFDs, and exceptFDs descriptor sets.
  <-> readFDs
 Pointer to 32-bit NetFDSetType containing set of bits representing descriptors to check for input.
  <-> writeFDs
 Pointer to 32-bit NetFDSetType containing set of bits representing descriptors to check for output.
  <-> exceptFDs
 Pointer to 32-bit NetFDSetType containing set of bits representing descriptors to check for exception conditions. This parameter is ignored. Upon return, its bits are always cleared.
  -> timeout
 Maximum timeout in system ticks; -1 means wait forever.
  <- errP
 Contains an error code if the return value is -1.

Result

Returns the sum total number of ready file descriptors in *readFDs, *writeFDs, and *exceptFDs. Returns 0 upon timeout. If the return value is -1, an error has occurred, and errP contains one of the following values:
  0
 No error
  netErrTimeout
 Call timed out.
  netErrNotOpen
 The referenced net library has not been opened yet.

Sockets Equivalent

int select (int width, fd_set* readfds, fd_set* writefds, fd_set* exceptfds, struct timeval* timeout);

Comments

This call blocks until one or more descriptors are ready for I/O. In the Palm OS environment, a descriptor is either a NetSocketRef or the "stdin" descriptor, sysFileDescStdIn. The sysFileDescStdIn descriptor will be ready for input whenever a user event is available like a pen tap or key press.

The caller should set which bits in each descriptor set need to be checked by using the netFDZero and netFDSet macros. After this call returns, the macro netFDIsSet can be used to determine which descriptors in each set are actually ready.

On exit, the total number of ready descriptors is returned and each descriptor set is updated with the appropriate bits set for each ready descriptor in that set.

The following example illustrates how to use this call to check for input on a socket or a user event:
    Err err;
    NetSocketRef socket;
    NetFDSetType readFDs,writeFDs,exceptFDs;
    Int16 numFDs;
    UInt16 width;

    // Create the descriptor sets
    netFDZero(&readFDs);
    netFDZero(&writeFDs);
    netFDZero(&exceptFDs);
    netFDSet(sysFileDescStdIn, &readFDs);
    netFDSet(socket, &readFDs);

    // Calculate the max descriptor number and
    // use that +1 as the max width.
    // Alternatively, we could simply use the
    // constant netFDSetSize as the width which
    // is simpler but makes the NetLibSelect call
    // slightly slower.
    width = sysFileDescStdIn;
    if (socket > width) width = socket;

    // Wait for any one of the descriptors to be
    // ready.
    numFDs = NetLibSelect(AppNetRefnum, width+1,
    &readFDs, &writeFDs, &exceptFDs,
    AppNetTimeout, &err);

Also see the NetSample example application in the Palm OS Examples folder. The function CmdTelnet in the file CmdTelnet.c shows how to use the Berkeley sockets select function and how to interpret the results.

See Also

NetLibSocketOptionSet



NetLibSend

Purpose

Send data to a socket from a single buffer.

Prototype

Int16 NetLibSend (UInt16 libRefNum, NetSocketRef socket, void* bufP, UInt16 bufLen, UInt16 flags, void* toAddrP, UInt16 toLen, Int32 timeout, Err* errP)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> socket
 Descriptor for the open socket.
  -> bufP
 Pointer to data to write.
  -> bufLen
 Length of data to write
  -> flags
 One or more netIOFlagxxx flags. See "I/O Flags."
  -> toAddrP
 Address to send to (a pointer to a NetSocketAddrType), or 0.
  -> toLen
 Size of toAddrP buffer.
  -> timeout
 Maximum timeout in system ticks; -1 means wait forever.
  <- errP
 Contains an error code if the return value is -1.

Result

Returns the number of bytes successfully sent. Returns 0 if the socket has been shut down by the remote host. If the return value is -1, an error has occurred, and errP contains one of the following values:
  0
 No error.
  netErrTimeout
 Call timed out.
  netErrNotOpen
 The referenced net library has not been opened yet.

netErrParamErr

netErrSocketNotOpen

netErrMessageTooBig

netErrSocketNotConnected

netErrSocketClosedByRemote

netErrIPCantFragment

netErrIPNoRoute

netErrIPNoSrc

netErrIPNoDst

netErrIPktOverflow

netErrOutOfCmdBlocks

netErrOutOfPackets

netErrInterfaceNotFound

netErrInterfaceDown

netErrUnreachableDest

netErrNoMultiPktAddr

netErrWouldBlock

Sockets Equivalent

int sendto(int socket, const void* bufP, int bufLen, int flags, const void* toAddrP, int toLen);

int send(int socket, const void* bufP, int bufLen, int flags);

int write(int socket, const void* bufP, int bufLen,);

Comments

This call attempts to write data to the specified socket and returns the number of bytes actually sent, which may be less than or equal to the requested number of bytes. The data is passed in a single buffer that bufP points to.

For datagram sockets, you must only send a single packet at a time. If the data is too large to fit in a single UDP packet (1536 bytes), no data is sent and -1 is returned.

The toAddrP field applies only to datagram sockets without an existing connection. An error is returned if the datagram socket was previously connected and toAddrP is specified. Stream-based sockets, by definition, must have a connection established with a remote host before data can be written. Raw sockets (supported in Palm OS version 3.0 and higher) must construct the entire IP header, including the destination address, before data can be sent; thus, the address is taken from the data to be sent.

If there isn't enough buffer space to send any data, this call will block until there is enough buffer space, or until a timeout.
NOTE:  

For stream-based sockets, this call may write only a portion of the desired data. It always returns the number of bytes actually written. Consequently, the caller should be prepared to call this routine repeatedly until the desired number of bytes have been written, or until it returns 0 or -1.

See Also

NetLibSendPB, NetUWriteN, NetLibReceive, NetLibReceivePB, NetLibDmReceive



NetLibSendPB

Purpose

Send data to a socket from a scatter-write array.

Prototype

Int16 NetLibSendPB (UInt16 libRefnum, NetSocketRef socket, NetIOParamType* pbP, UInt16 flags, Int32 timeout, Err* errP)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> socket
 Descriptor for the open socket.
  -> pbP
 Pointer to parameter block containing buffer info. See the description in NetLibReceivePB.
  -> flags
 One or more netIOFlagxxx flags. See "I/O Flags."
  -> timeout
 Maximum timeout in system ticks; -1 means wait forever.
  <- errP
 Contains an error code if the return value is -1.

Result

Returns the number of bytes successfully sent. Returns 0 if the socket has been shut down by the remote host. If the return value is -1, an error has occurred, and errP contains one of the following values:
  0
 No error.
  netErrTimeout
 Call timed out.
  netErrNotOpen
 The referenced net library has not been opened yet.

netErrParamErr

netErrSocketNotOpen

netErrMessageTooBig

netErrSocketNotConnected

netErrSocketClosedByRemote

netErrIPCantFragment

netErrIPNoRoute

netErrIPNoSrc

netErrIPNoDst

netErrIPktOverflow

netErrOutOfCmdBlocks

netErrOutOfPackets

netErrInterfaceNotFound

netErrInterfaceDown

netErrUnreachableDest

netErrNoMultiPktAddr

netErrWouldBlock

Sockets Equivalent

int sendmsg(int socket, const struct msghdr* pbP, int flags);

Comments

This call attempts to write data to the given socket and returns the number of bytes actually sent, which may be less than or equal to the requested number of bytes. The data is passed in the scatter-write array specified in the pbP parameter block.

For datagram sockets, you must only send a single packet at a time. If the data is too large to fit in a single UDP packet, no data is sent and -1 is returned.

The toAddrP field applies only to datagram sockets without an existing connection. An error is returned if the datagram socket was previously connected and toAddrP is specified. Stream-based sockets, by definition, must have a connection established with a remote host before data can be written. Raw sockets (supported in Palm OS version 3.0 and higher) must construct the entire IP header, including the destination address, before data can be sent; thus, the address is taken from the data to be sent.

If there isn't enough buffer space to send any data, this call will block until there is space, or until a timeout.
NOTE:  

For stream-based sockets, this call may write only a portion of the desired data. It always returns the number of bytes actually written. Consequently, the caller should be prepared to call this routine repeatedly until the desired number of bytes have been written, or until it returns 0 or -1.

See Also

NetLibSend, NetLibReceive, NetLibReceivePB, NetLibDmReceive



NetLibSettingGet

Purpose

Retrieves a general setting.

Prototype

Err NetLibSettingGet (UInt16 libRefnum, UInt16 setting, void* valueP, UInt16* valueLenP)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> setting
 Setting to retrieve, one of the NetSettingEnum constants.
  <- valueP
 Space for return value of setting.
  <-> valueLenP
 On entry, size of valueP. On exit, actual size of setting.

Result

Returns one of the following values:
  0
 Success.
  netErrUnknownSetting
 Invalid setting constant
  netErrPrefNotFound
 No current value for setting
  netErrBufTooSmall
 valueP was too small to hold entire setting. Setting value was truncated to fit in valueP.
 

Sockets Equivalent

None

Comments

This call retrieves the current value of any general setting. The caller must pass a pointer to a buffer to hold the return value (valueP), the size of the buffer (*valueLenP), and the setting ID (setting). The setting ID is one of the NetSettingEnum constants in the netSettingEnum type.

Some settings, such as the host table, are variable size. For these types of settings, you can obtain the actual size required for the buffer by passing 0 for *valueLenP. The required size is returned in valueLenP.

Table 54.2 lists the general settings and the type of each setting.

Table 54.2 Net Library General Settings 
netSetting... Type Description
ResetAll void Used for NetLibSettingSet only. This will clear all other settings to their default values.
PrimaryDNS UInt32 IP address of primary DNS server. This setting must be set to a non-zero IP address in order to support any of the name lookup calls.
SecondaryDNS UInt32 IP address of secondary DNS server. Set to 0 to have stack ignore this setting.
DefaultRouter UInt32 IP address of default router. Default value is 0 which is appropriate for most implementations with only one attached interface (besides loopback). Packets with destination IP addresses that don't lie in the subnet of an attached interface will be sent to this router through the default interface specified by the netSettingDefaultIFCreator/netSettingDefaultIFInstance pair.
DefaultIFCreator UInt32 Creator of the default network interface. Default value is 0, which is appropriate for most implementations. Packets with destination IP addresses that don't lie in the subnet of a directly attached interface are sent through this interface. If this setting is 0, the stack automatically makes the first non-loopback interface the default interface.
DefaultIFInstance UInt16 Instance number of the default network interface. Packets with destination IP addresses that don't lie in the subnet of an attached interface are sent through the default interface. Default value is 0.
HostName Char[] A zero-terminated character string of 64 bytes or less containing the host name of this machine. This setting is not actually used by the stack. It's present mainly for informative purposes and to support the gethostname/sethostname sockets API calls. To clear the host name, call NetLibIFSettingSet with a valueLen of 0.
DomainName Char[] A zero-terminated character string of 256 bytes or less containing the default domain. This default domain name is appended to all host names before name lookups are performed. If the name is not found, the host name is looked up again without appending the domain name to it. To have the stack not use the domain name, call NetLibIFSettingSet with a valueLen of 0.
HostTbl Char[] A null-terminated character string containing the host table. This table is consulted first before sending a DNS query to the DNS server(s). To have the stack not use a host table, call NetLibIFSettingSet with a valueLen of 0. The format of a host table is a series of lines separated by `\n' in the following format:

host.company.com A 111.222.333.444
CloseWaitTime UInt32 The close-wait time in milliseconds. This setting must be specified. See the discussion of the NetLibClose call for an explanation of the close-wait time.
TraceBits UInt32 A bitfield of various trace bits. See "Tracing Bits." Default value is (netTracingErrors | netTracingAppMsgs). An application can get a list of events in the trace buffer using the NetLibMaster call.
TraceSize UInt32 Maximum trace buffer size in bytes. Setting this setting always clears the existing trace buffer. Default is 2 KB.
TraceRoll UInt8 Boolean value, default is true (non-zero). If true, trace buffer will roll over when it fills. If false, tracing will stop as soon as trace buffer fills.

See Also

NetLibSettingSet, NetLibIFSettingSet, NetLibIFSettingGet, NetLibMaster



NetLibSettingSet

Purpose

Sets a general setting.

Prototype

Err NetLibSettingSet (UInt16 libRefnum, UInt16 setting, void* valueP, UInt16 valueLen)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> setting
 Setting to set; one of the NetSettingEnum constants. See Table 54.2.
  -> valueP
 New value for the setting.
  -> valueLen
 Size of new setting.

Result

Returns one of the following values:
  0
 Success.
  netErrUnknownSetting
 Invalid setting constant.
  netErrInvalidSettingSize
 valueLen was invalid for the given setting.
  netErrBufTooSmall
 valueP was too small to hold entire setting. Setting value was truncated to fit in valueP.
 

 

Sockets Equivalent

None

Comments

This call can be used to set the current value of any general setting. The caller must pass a pointer to a buffer which holds the new value (valueP), the size of the buffer (valueLen), and the setting ID (setting). The setting ID is one of the netSettingXXX constants in the NetSettingEnum type.

See NetLibSettingGet for an explanation of each of the settings.

Of particular interest is the netSettingResetAll setting, which, if used, will reset all general settings to their default values. When using this setting, valueP and valueLen are ignored.

See Also

NetLibSettingGet, NetLibSettingSet, NetLibIFSettingSet, NetLibMaster



NetLibSocketAccept

Purpose

Accept a connection from a stream-based socket.

Prototype

Int16 NetLibSocketAccept (UInt16 libRefnum, NetSocketRef socket, NetSocketAddrType* sockAddrP, Int16* addrLenP, Int32 timeout, Err* errP)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> socket
 Descriptor for the open socket.
  <- sockAddrP
 Address of remote host is returned here.
  <->addrLenP
 On entry, length of sockAddrP buffer in bytes. On exit, length of returned address stored in *sockAddrP.
  -> timeout
 Maximum timeout in system ticks; -1 means wait forever.
  <- errP
 Contains an error code if the return value is -1.

Result

Returns the NetSocketRef of the new socket. If the return value is -1, an error has occurred, and errP contains one of the following values:
  0
 No error.
  netErrTimeout
 Call timed out.
  netErrNotOpen
 The referenced net library has not been opened yet.

netErrParamErr

netErrSocketNotOpen

netErrSocketNotConnected

netErrSocketClosedByRemote

netErrWrongSocketType

netErrSocketNotListening

netErrUnimplemented

Sockets Equivalent

int accept (int socket, void* sockAddrP, int* addrLenP);

Comments

Accepts the next connection request from a remote client. This call is only applicable to stream-based sockets. Before calling NetLibSocketAccept on a socket, a server application needs to:

NetLibSocketAccept will block until a successful connection request is obtained from a remote client. After a successful connection is made, this call returns with the address of the remote host in *sockAddrP and the socket descriptor of a new socket as the return value. You then use the new socket to send and receive data.

See Also

NetLibSocketBind, NetLibSocketListen



NetLibSocketAddr

Purpose

Returns the local and remote addresses currently associated with a socket.

Prototype

Int16 NetLibSocketAddr (UInt16 libRefnum, NetSocketRef socketRef, NetSocketAddrType* locAddrP, Int16* locAddrLenP, NetSocketAddrType* remAddrP, Int16* remAddrLenP, Int32 timeout, Err* errP)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> socketRef
 Descriptor for the open socket.
  <- locAddrP
 Local address of socket is returned here.
  <->locAddrLenP
 On entry, length of locAddrP buffer in bytes. On exit, length of returned address stored in *locAddrP.
  <- remAddrP
 Address of remote host is returned here.
  <->remAddrLenP
 On entry, length of remAddrP buffer in bytes. On exit, length of returned address stored in *remAddrP.
  -> timeout
 Maximum timeout in system ticks; -1 means wait forever.
  <- errP
 Contains an error code if the return value is -1.

Result

Returns 0 upon success and -1 if an error occurred. If the return value is -1, errP contains one of the following values:
  0
 No error.
  netErrTimeout
 Call timed out.
  netErrNotOpen
 The referenced net library has not been opened yet.

netErrParamErr

netErrSocketNotOpen

netErrSocketClosedByRemote

netErrOutOfCmdBlocks

Sockets Equivalent

int getpeername (int s, struct sockaddr* name, int* namelen);

int getsockname (int s, struct sockaddr* name, int* namelen);

Comments

This call is mainly useful for stream-based sockets. It allows the caller to find out what address was bound to a connected socket and the address of the remote host that it's connected to.

In Palm OS version 3.0 and higher, if you pass a raw socket to this function, it returns the instance number and creator of the interface to which the socket is bound.

See Also

NetLibSocketBind, NetLibSocketConnect, NetLibSocketAccept



NetLibSocketBind

Purpose

Assign a local address to a socket.

Prototype

Int16 NetLibSocketBind (UInt16 libRefnum, NetSocketRef socket, NetSocketAddrType* sockAddrP, Int16 addrLen, Int32 timeout, Err* errP)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> socket
 Descriptor for the open socket.
  -> sockAddrP
 Pointer to the address to give to the socket. This can be a NetSocketAddrINType or a NetSocketAddrRawType.
  -> addrLen
 Length of address in *sockAddrP.
  -> timeout
 Maximum timeout in system ticks; -1 means wait forever.
  <- errP
 Contains an error code if the return value is -1.

Result

Returns 0 upon success and -1 if an error occurred. If an error occurred, errP contains one of the following values:
  0
 No error.
  netErrTimeout
 Call timed out.
  netErrNotOpen
 The referenced net library has not been opened yet.

netErrParamErr

netErrSocketNotOpen

netErrSocketAlreadyConnected

netErrSocketClosedByRemote

netErrOutOfCmdBlocks

Sockets Equivalent

int bind (int socket, const void* sockAddrP, int addrLen);

Comments

Applications that want to wait for an incoming connection request from a remote host must call this function. After calling NetLibSocketBind, applications can call NetLibSocketListen and then NetLibSocketAccept to make the socket ready to accept connection requests.

Compatibility

Raw sockets are only supported in Palm OS version 3.0 and higher. See NetLibSocketOpen for instructions on how to bind raw sockets.

See Also

NetLibSocketConnect, NetLibSocketListen, NetLibSocketAccept



NetLibSocketClose

Purpose

Close a socket.

Prototype

Int16 NetLibSocketClose (UInt16 libRefnum, NetSocketRef socket, Int32 timeout, Err* errP)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> socket
 Descriptor for the open socket.
  -> timeout
 Maximum timeout in system ticks; -1 means wait forever.
  <- errP
 Contains an error code if the return value is -1.

Result

Returns 0 upon success and -1 if an error occurred. If an error occurred, errP contains one of the following values:
  0
 No error.
  netErrTimeout
 Call timed out.
  netErrNotOpen
 The referenced net library has not been opened yet.

netErrParamErr

netErrSocketNotOpen

netErrOutOfCmdBlocks

Sockets Equivalent

int close(int socket);

Comments

Closes down a socket and frees all memory associated with it.

See Also

NetLibSocketOpen, NetLibSocketShutdown



NetLibSocketConnect

Purpose

Assign a destination address to a socket and initiate three-way handshake if it's stream based.

Prototype

Int16 NetLibSocketConnect (UInt16 libRefnum, NetSocketRef socket, NetSocketAddrType* sockAddrP, Int16 addrLen, Int32 timeout, Err* errP)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> socket
 Descriptor for the open socket.
  -> sockAddrP
 Pointer to address to connect to.
  -> addrLen
 Length of address in *sockAddrP.
  -> timeout
 Maximum timeout in system ticks; -1 means wait forever.
  <- errP
 Contains an error code if the return value is -1.

Result

Returns 0 upon success and -1 if an error occurred. If an error occurred, errP contains one of the following values:
  0
 No error.
  netErrTimeout
 Call timed out.
  netErrNotOpen
 The referenced net library has not been opened yet.

netErrParamErr

netErrSocketNotOpen

netErrSocketBusy
  netErrNoInterfaces
 Incorrect setup.

netErrPortInUse

netErrQuietTimeNotElapsed

netErrInternal

netErrSocketAlreadyConnected

netErrSocketClosedByRemote

netErrTooManyTCPConnections

netErrWouldBlock

netErrWrongSocketType

netErrOutOfCmdBlocks

Sockets Equivalent

int connect (int socket, const void* sockAddrP, int addrLen);

See Also

NetLibSocketBind, NetUTCPOpen



NetLibSocketListen

Purpose

Put a stream-based socket into passive listen mode.

Prototype

Int16 NetLibSocketListen (UInt16 libRefnum, NetSocketRef socket, UInt16 queueLen, Int32 timeout, Err* errP)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> socket
 Descriptor for the open socket.
  -> queueLen
 Maximum number of pending connections allowed.
  -> timeout
 Maximum timeout in system ticks; -1 means wait forever.
  <- errP
 Contains an error code if the return value is -1.

Result

Returns 0 upon success and -1 if an error occurred. If an error occurred, errP contains one of the following values:
  0
 No error.
  netErrTimeout
 Call timed out.
  netErrNotOpen
 The referenced net library has not been opened yet.

netErrParamErr

netErrOutOfResources

netErrSocketNotOpen

netErrSocketBusy
  netErrNoInterfaces
 Incorrect setup.

netErrPortInUse

netErrInternal

netErrSocketAlreadyConnected

netErrSocketClosedByRemote

netErrWrongSocketType

netErrQuietTimeNotElapsed

netErrOutOfCmdBlocks

Sockets Equivalent

int listen (int socket, int queueLen);

Comments

Sets the maximum allowable length of the queue for pending connections. This call is only applicable to stream-based (TCP/IP) sockets.

After a socket is created and bound to a local address using NetLibSocketBind, a server application can call NetLibSocketListen and then NetLibSocketAccept to accept connections from remote clients.

The queueLen is currently quietly limited to 1 (higher values are ignored).

See Also

NetLibSocketBind, NetLibSocketAccept



NetLibSocketOpen

Purpose

Open a new socket.

Prototype

NetSocketRef NetLibSocketOpen (UInt16 libRefnum, NetSocketAddrEnum domain, NetSocketTypeEnum type, Int16 protocol, Int32 timeout, Err* errP)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> domain
 Address domain. See NetSocketAddrEnum.
  -> type
 Desired type of connection. See NetSocketTypeEnum.
  -> protocol
 Protocol to use. This parameter is currently ignored.
 
For raw sockets in the netSocketAddrINET domain, specify one of the following:
 

 

 

 
For all other socket types or for raw sockets in the raw domain, this parameter is ignored.
  -> timeout
 Maximum timeout in system ticks; -1 means wait forever.
  <- errP
 Contains an error code if the return value is -1.

Result

Returns the NetSocketRef of the opened socket or -1 if an error occurred. If an error occurred, errP contains one of the following values:
  0
 No error.
  netErrTimeout
 Call timed out.
  netErrNotOpen
 The referenced net library has not been opened yet.

netErrParamErr

netErrNoMoreSockets

netErrOutOfCmdBlocks

netErrOutOfMemory

Sockets Equivalent

int socket(int domain, int type, int protocol);

Comments

Allocates memory for a new socket and opens it.

Raw sockets are supported in Palm OS version 3.0 and higher. Two types of raw sockets are supported:

  • Raw sockets in the netSocketAddrINET domain

    In this case, you must bind the socket to an IP address using NetLibSocketBind, passing a NetSocketAddrINType structure for the socket address. The port field is ignored.

    For applications that use raw sockets in the INET domain, the net library checks the destination IP address of all incoming packets to see if it matches any of those raw sockets. If it does, the packet is enqueued directly into the matching socket and is not passed to the protocol stack.

    When an application sends data through raw sockets in the IP domain, the net library packages the data into a packet and passes it directly to the interface's send routine. You are responsible for forming the entire IP header, including any necessary checksums, source and destination IP address, and so on.

  • Raw sockets in the netSocketAddrRaw domain with no protocol

    In this case, you must bind the socket to an interface using NetLibSocketBind, passing a NetSocketAddrRawType structure for the socket address. The instance and creator specify which interface the caller wants to receive raw packets from.

    When an interface is bound to a raw socket with no protocol, the net library places that interface into raw mode. In raw mode, the interface passes all incoming packets, no matter what the link layer protocol, to its raw receive function.

    When an application sends data through a raw socket with no protocol, the net library packages the data into a packet and passes it directly to the interface's send routine.

    The interface remains in raw mode until the raw socket is closed.

Compatibility

Raw sockets supported only in Palm OS version 3.0 and higher.

See Also

NetLibSocketClose, NetUTCPOpen



NetLibSocketOptionGet

Purpose

Retrieves the current value of a socket option.

Prototype

Int16 NetLibSocketOptionGet (UInt16 libRefnum, NetSocketRef socket, UInt16 level, UInt16 option, void* optValueP, UInt16 * optValueLenP, Int32 timeout, Err* errP)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> socket
 Descriptor for the open socket.
  -> level
 Level of the option, one of the NetSocketOptLevelEnum constants. See NetLibSocketOptionSet.
  -> option
 One of the NetSocketOptEnum constants. See NetLibSocketOptionSet.
  <- optValueP
 Pointer to variable holding new value of option.
  <-> optValueLenP
 Size of variable pointed to by optValueP on entry. Actual size of return value on exit.
  -> timeout
 Maximum timeout in system ticks; -1 means wait forever.
  <- errP
 Contains an error code if the return value is -1.

Result

Returns 0 upon success and -1 if an error occurred. If an error occurred, errP contains one of the following values:
  0
 No error.
  netErrTimeout
 Call timed out.
  netErrNotOpen
 The referenced net library has not been opened yet.

netErrParamErr

netErrSocketNotOpen

netErrUnimplemented

netErrWrongSocketType

netErrInvalidSettingSize

Sockets Equivalent

int getsockopt (int socket, int level, int option, const void* optValueP, int* optValueLenP);

Comments

Returns the current value of a socket option. The caller passes a pointer to a variable to hold the returned value (in optValueP) and the size of this variable (in *optValueLenP). On exit, *optValueP is updated with the actual size of the return value.

For all of the fixed size options (every option except netSocketOptIPOptions), *optValueLenP is unmodified on exit and this call does its best to return the value in the caller's desired type size.

For compatibility with existing Internet applications, this call is quite flexible on the *optValueLenP parameter. If the desired type for an option is FLAG, this call supports an *optValueLenP of 1, 2, or 4. If the desired type for an option is int, it supports an *optValueLenP of 2 or 4.

See NetLibSocketOptionSet for a list of available options.

See Also

NetLibSocketOptionSet



NetLibSocketOptionSet

Purpose

Set a socket option.

Prototype

Int16 NetLibSocketOptionSet (UInt16 libRefnum, NetSocketRef socket, UInt16 level, UInt16 option, void* optValueP, UInt16 optValueLen, Int32 timeout, Err* errP)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> socket
 Descriptor for the open socket.
  -> level
 Level of the option, one of the NetSocketOptLevelEnum constants. See the comments section.
  -> option
 One of the NetSocketOptEnum constants. See the comments section.
  -> optValueP
 Pointer to the variable holding the new value of the option.
  -> optValueLen
 Size of variable pointed to by optValueP.
  -> timeout
 Maximum timeout in system ticks; -1 means wait forever.
  <- errP
 Contains an error code if the return value is -1.

Result

Returns 0 upon success and -1 if an error occurred. If an error occurred, errP contains one of the following values:
  0
 No error.
  netErrTimeout
 Call timed out.
  netErrNotOpen
 The referenced net library has not been opened yet.

netErrParamErr

netErrSocketNotOpen

netErrUnimplemented

netErrWrongSocketType

netErrInvalidSettingSize

Sockets Equivalent

int setsockopt (int socketRef, int level, int option, const void* optValueP, int optValueLen);

Comments

Sets various options associated with a socket. The caller passes a pointer to the new option value in optValueP and the size of the option in optValueLen.

Table 54.3 lists the available options.

  • The Level column specifies the option level, which is one of the netSocketOptLevelXXX constants.

  • The Option column lists the option, which is one of the netSocketOptXXX constants.

  • The G/S column lists whether this option can be fetched with the NetLibSocketOptionGet call (G) and/or set (S) with this call.

  • The type column lists the data type of the option.

  • The I column specifies whether or not this option is currently implemented.

    Table 54.3 Net Library Socket Options 
    netSocket
    OptLevel...
    netSocketOpt...
    G/S
    Type
    I
    Description
    IP IPOptions GS UInt8[] N Options in IP Header
    TCP TCPNoDelay GS FLAG Y Don't delay send to coalesce packets
    TCP TCPMaxSeg G int Y Get TCP maximum segment size
    Socket SockDebug GS FLAG N Turn on recording of debug info
    Socket SockAcceptConn G FLAG N Socket has had listen
    Socket SockReuseAddr GS FLAG N Allow local address reuse
    Socket SockKeepAlive GS FLAG Y Keep connections alive
    Socket SockDontRoute GS FLAG N Just use interface addresses
    Socket SockBroadcast GS FLAG N Permit sending of broadcast messages
    Socket SockUseLoopback GS FLAG N Bypass hardware when possible
    Socket SockLinger GS NetSocket
    LingerType     		Y Linger on close if data present NetSocketLingerType is a structure with two fields: onOff (true or false) and time (linger time in seconds).
    Socket SockOOBInLine GS FLAG N Leave received OOB data in-line
    Socket SockSndBufSize GS int N Send buffer size
    Socket SockRcvBufSize GS int N Receive buffer size
    Socket SockSndLowWater GS int N Send low-water mark
    Socket SockRcvLowWater GS int N Receive low-water mark
    Socket SockSndTimeout GS int N Send timeout
    Socket SockRcvTimeout GS int N Receive timeout
    Socket SockErrorStatus G int Y Get error status and clear
    Socket SockSocketType G int Y Get socket type
    Socket SockNonBlocking GS FLAG Y Set non-blocking mode on/off

For compatibility with existing Internet applications, this call is quite flexible on the optValueLen parameter. If the desired type for an option is FLAG, this call accepts an optValueLen of 1, 2, or 4. If the desired type for an option is int, it accepts an optValueLen of 2 or 4.

Except for the netSocketOptSockNonBlocking option, all options listed above have equivalents in the sockets API. The netSocketOptSockNonBlocking option was added to this call in the net library in order to implement the functionality of the UNIX fcntl() control call, which can be used to turn nonblocking mode on and off for sockets.

See Also

NetLibSocketOptionGet



NetLibSocketShutdown

Purpose

Shut down a socket in one or both directions.

Prototype

Int16 NetLibSocketShutdown (UInt16 libRefnum, NetSocketRef socket, Int16 direction, Int32 timeout, Err* errP)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> socket
 Descriptor for the open socket.
  -> direction
 Direction to shut down. One of the NetSocketDirEnum constants. Specifically:
  netSocketDirInputnetSocketDirOutput
 netSocketDirInputnetSocketDirOutputnetSocketDirBoth
  -> timeout
 Maximum timeout in system ticks; -1 means wait forever.
  <- errP
 Contains an error code if the return value is -1.

Result

Returns 0 upon success and -1 if an error occurred. If an error occurred, errP contains one of the following values:
  0
 No error.
  netErrTimeout
 Call timed out.
  netErrNotOpen
 The referenced net library has not been opened yet.

netErrParamErr

netErrSocketNotOpen

netErrNoMultiPktAddr

netErrOutOfCmdBlocks

Sockets Equivalent

int shutdown (int socket, int direction);

Comments

Shuts down communication in one or both directions on a socket.

If direction is netSocketDirInput, the socket is marked as down in the receive direction and further read operations from it return a netErrSocketInputShutdown error.



NetLibTracePrintF

Purpose

Store debugging information in the net library's trace buffer.

Prototype

Err NetLibTracePrintF (UInt16 libRefnum, Char *formatStr, ...)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> formatStr
 A printf style format string.
  -> ...
 Arguments to the format string.

Result

Returns 0 upon success or netErrNotOpen if the net library has not been opened.

Sockets Equivalent

None

Comments

This call is a convenient debugging tool for developing Internet applications. It stores a message into the net library's trace buffer, which can later be dumped using the NetLibMaster call. The net library's trace buffer is used to store run-time errors that the net library encounters as well as errors and messages from network interfaces and from applications that use this call.

The formatStr parameter is a printf style format string which supports the following format specifiers:

%d, %i, %u, %x, %s, %c

but it does not support field widths, leading 0's etc.

Note that the netTracingAppMsgs bit of the netSettingTraceBits setting must be set using the call NetLibSettingSet(...netSettingTraceBits...). Otherwise, this routine will do nothing.

See Also

NetLibTracePutS, NetLibMaster, NetLibSettingSet



NetLibTracePutS

Purpose

Store debugging information in the net library's trace buffer.

Prototype

Err NetLibTracePutS (UInt16 libRefnum, Char *strP)

Parameters

  -> libRefNum
 Reference number of the net library.
  -> strP
 String to store in the trace buffer.

Result

Returns 0 upon success or netErrNotOpen if the net library has not been opened.

Sockets Equivalent

None

Comments

This call is a convenient debugging tool for developing Internet applications. It will store a message into the net library's trace buffer which can later be dumped using the NetLibMaster call. The net library's trace buffer is used to store run-time errors that the net library encounters as well as errors and messages from network interfaces and from applications that use this call.

Note the netTracingAppMsgs bit of the netSettingTraceBits setting must be set using the NetLibSettingSet(...netSettingTraceBits...) call or this routine will do nothing.

See Also

NetLibTracePrintF, NetLibMaster, NetLibSettingSet.



NetNToHL

Purpose

Macro that converts a 32-bit value from network to host byte order.

Prototype

NetNToHL (x)

Parameters

  -> x
 32-bit value to convert.

Result

Returns x in host byte order.

Errors

none

Sockets Equivalent

ntohl()

See Also

NetNToHS, NetHToNL, NetHToNS



NetNToHS

Purpose

Macro that converts a 16-bit value from network to host byte order.

Prototype

NetNToHS (x)

Parameters

  -> x
 16-bit value to convert.

Result

Returns x in host byte order.

Errors

None

Sockets Equivalent

ntohs()

See Also

NetHToNL, NetNToHL, NetHToNS


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