ACC Programmer's Reference Guide

Chapter 4 145
ZCOM C I/F Library Routines
LTQDGET (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
Normally, the data queue number used s hould be allocated by ZMON
(see the zltqueue ma n page for how to get a data queue number). There is
no queue ownership validation within this routine; it is up to the user to
make sure that the queue usage is valid and consistent.
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 of a terminal from which to get the
data.
queue Terminal data queue number (specifies which data
queueistobeused).
0 - Sub-packet holding queue (reserved)
1 - Data holding queue A
2 - Data holding queue B
3 - Data holding queue C
4 - Data holding queue D
ibuf (Return Param) On a successful return, the data is placed into this
buffer.
len Length in bytes of ibuf.
rlenp (Return Param) Actual number of bytes returned in ibuf.