ZCOM C I/F Library Routines

ZQSZE (3X)

 

ZQSZE (3X)

NAME

zqsze – Read ZLU input queue size

SYNOPSIS

#include

<zcom/zcomsys.h>

#include

<zcom/zcomcall.h> /* if compiled with ANSI C (recommended) */

int32 zqsze (zap, zqhdp)

zaddr_type *zap; zqhd_type *zqhdp;

DESCRIPTION

Routine zqsze will return the queue header information, which includes

 

the number of messages, i.e., the number of buffers (zqhd_type->qnmsg)

 

queued to the specified program ZLU. An error is returned if the ZLU is

 

not a program ZLU.

 

 

The libraries libzcom_c.a and libpthread.a must be linked into the calling

 

program by giving the options “-lzcom_c -lpthread” to cc(1) or ld(1).

Threads

This routine may be called from a multi-threaded application using the

Considerations

POSIX (1003.1c) kernel threads API package. This routine has the

 

following characteristics when called by a multi-threaded application:

 

cancellation point

Thread cancellation can occur when a thread

 

 

calls this routine.

 

async-cancel unsafe

The calling thread’s cancelability type must be

 

 

PTHREAD_CANCEL_DEFERRED if

 

 

cancellation is enabled.

 

async-signal unsafe

It cannot be called from a signal handler.

 

fork unsafe

It cannot be called by a child process after

 

 

fork(2) but before exec(2).

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Chapter 4