putpmsg System Call

Communications Technical Reference, Volume 2

putpmsg System Call

Purpose

Sends a priority message on a stream.

Syntax

#include <stropts.h>

int putpmsg (fd, ctlptr, 
dataptr, band, flags)
int fd;
struct strbuf *ctlptr;
struct strbuf *dataptr;
int band;
int flags;

Description

The putpmsg system call is identical to the putmsg system call except that it sends a priority message. All information except for flag settings are found in the description for the putmsg system call. The differences in the flag settings are noted in the error codes section.

Parameters

Specifies a file descriptor referencing an open stream.

ctlptr

Holds the control part of the message.

dataptr

Holds the data part of the message.

band

Indicates the priority band.

flags

Indicates the priority type of message to be sent. Acceptable values are:

MSG_BAND	Sends a non-priority message.
MSG_HIPRI	Sends a priority message.

Error Codes

The putpmsg system call is unsuccessful under the following conditions:

The flags parameter is set to a value of 0.
The flags parameter is set to MSG_HIPRI and the band parameter is set to a nonzero value.
The flags parameter is set to MSG_HIPRI and no control part is specified.

Implementation Specifics

This system call is part of STREAMS Kernel Extensions.

Related Information

The poll subroutine, read subroutine, write subroutine.

The getmsg system call, getpmsg system call, putmsg system call.

List of Streams Programming References and STREAMS Overview in AIX Version 4.3 Communications Programming Concepts, and X/OPEN Common Application Environment (CAE) Specification: System Interfaces and Headers, Issue 5 (2/97).