Section: POSIX Programmer's Manual (3P)
This manual page is part of the POSIX Programmer's Manual.
The Linux implementation of this interface may differ (consult
the corresponding Linux manual page for details of Linux behavior),
or the interface may not be implemented on Linux.
--- suspend the thread until a signal is received
function shall suspend the calling thread until delivery of a signal
whose action is either to execute a signal-catching function or to
terminate the process.
If the action is to terminate the process,
shall not return.
If the action is to execute a signal-catching function,
shall return after the signal-catching function returns.
suspends thread execution indefinitely unless interrupted by a signal,
there is no successful completion return value. A value of -1 shall
be returned and
set to indicate the error.
function shall fail if:
A signal is caught by the calling process and control is returned from
the signal-catching function.
The following sections are informative.
Many common uses of
have timing windows. The scenario involves checking a condition
related to a signal and, if the signal has not occurred, calling
When the signal occurs between the check and the call to
the process often blocks indefinitely. The
functions can be used to avoid this type of problem.
The Base Definitions volume of POSIX.1-2017,
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1-2017, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 7, 2018 Edition,
Copyright (C) 2018 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group.
In the event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online at
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