ZMAPR (3X)

NAME

zmapr - Set up ZLU mapping configuration

SYNOPSIS

#include  <zcom/zcomsys.h>
#include  <zcom/zcomcall.h> /* if compiled with ANSI C (recommended) */
 
int32 zmapr (zap, mzap)
 
zaddr_type   *zap; 
zaddr_type   *mzap;

DESCRIPTION

Routine zmapr is used to set up an alternate mapping for a ZLU. After the zmapr routine has been successfully called, all messages addressed to the source ZLU (*zap) will be redirected to the destination ZLU (*mzap).

Both ZLUs must be an existing ZLU such as a:

- program ZLU returned from zopen,

- terminal ZLU pre-defined in the TTGEN configuration file,

- mapped ZLU used in previous zmapr calls.

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 Considerations

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

PARAMETERS

zap	ZCOM address to be mapped.
mzap	ZCOM address to be mapped onto.

NOTES

On a successful return from zmapr, accessing the source ZLU is actually directed to the destination ZLU. If the source ZLU was a program ZLU, all messages that were queued on it will be flushed (i.e., returned to the free queue). If it was a terminal ZLU, the linkage to the terminal is lost. Usually, this is not desirable because the previously associated terminal is unusable.

RETURN VALUE

Routine zmapr returns 0 if successful. Otherwise, a non-zero error code is returned. See /opt/acc/include/zcom/zcomsys.h for the list of ZCOM error codes and their meanings.

EXAMPLE

#include     <zcom/zcomsys.h>
#include     <zcom/zcomcall.h> 
 
int32          ierr;
zaddr_type     zaddr;
zaddr_type      maddr;
 
if (ierr = zmapr (&zaddr, &maddr)) {
     /* error return code */
}
else {
     /* good return code */
}

FILES

/opt/acc/include/zcom/zcomsys.h	ZCOM subsystem general include file, containing data types, data structures, constants, error codes, masks, etc. Note that this must be the first include file before any other ZCOM include files.
/opt/acc/include/zcom/zcomcall.h	ZCOM routine function prototypes (requires ANSI C compilation).