ACC Programmer's Reference Guide

238 Chapter4
ZCOM C I/F Library Routines
ZLTUP (3X)
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:
PARAMETERS
NOTES The offset returned by zltstore may be passed to zltup to update the
allocated storage area in the extension area. To update the fields in the
basic table, the offset may be worked out by the ZCOM_OFFSET macro
(defined in zcomsys.h). For example, to get the offset for the application
number field ltapno:
int32 offset;
zltt_type ltt, *lttp;
offset = ZCOM_OFFSET (*lttp, ltapno); <-- Both will work
offset = ZCOM_OFFSET (ltt, ltapno); <-- Both will work
RETURN VALUE Routine zltup 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.
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).
zap ZCOM address.
ibuf Data buffer.
len Byte length of buffer.
offset Byte offset within the logical terminal table where the data in the buffer
should be placed. See NOTES for information on finding the offsets.