ZX25INFO (3X) — ACC X.25

NAME

zx25info - Set up ACC X.25 information for subsequent "zx25..." calls

SYNOPSIS

#include   <zcom/zcomsys.h>
#include   <zcom/zcomx25.h>
 
int zx25info (zxip, auxname)
 
zx25info_type         *zxip;
char                  *auxname;

DESCRIPTION

Routine zx25info sets up the ACC X.25 access data structure which is used in subsequent "zx25..." calls. This routine may allocate some internal resources. The caller is required to call zx25close(3X) to clean up the allocated resources when the "zx25..." calls are no longer required.

The libraries libzx25.a, libzcom_c.a and libpthread.a must be linked into the calling program by giving the "-lzx25 -lzcom_c -lpthread" options 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. It has the following characteristics when called by multi-threaded applications:

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).

See the NOTES section that follows for more information on using this routine in a multi-threaded application.

PARAMETERS:

zxip (Return Param): Address of the user supplied ZCOM X.25 access data structure. On successful return, access information will be setup in this buffer. This data structure is then used in subsequent zx25...(3X) calls.
auxname: User supplied name to use for opening the response ZLU. The name must be unique within the local node. It may be a maximum of 7 characters long, plus a terminating NULL.

RETURN VALUE

Routine zx25info returns a 0 when successful. If there was a ZCOM error, it returns a negative value. See /opt/acc/include/zcom/zcomsys.h for the list of ZCOM error codes and their meanings.

NOTES

The auxname parameter is the ZLU name used to open the response ZLU. If multiple copies of a program will be run, this name should be made unique for each copy (for example, using the process ID to generate this name, or using the makezluname routine).
In a multi-threaded application, the threads cannot share a global ZCOM X.25 access data buffer zxip. To call zx25info, each thread must use a separate buffer and a different ZLU name. Normally, zx25info should be called AFTER a thread is generated, using a per-thread buffer.

EXAMPLE

#include    <zcom/zcomsys.h>
#include    <zcom/zcomx25.h>
 
int            ierr;
zx25info_type  zxi;
char           auxname[size]; /* size is user-defined */
 
if (ierr = zx25info (&zxi, auxname)) {
    /* 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/zcomx25.h: ZCOM X.25 access data structure declarations.