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PSELECT(2) FreeBSD System Calls Manual PSELECT(2)
NAME
pselect - synchronous I/O multiplexing a la POSIX.1g
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <sys/select.h>
int
pselect(int nfds, fd_set * restrict readfds, fd_set * restrict writefds,
fd_set * restrict exceptfds,
const struct timespec * restrict timeout,
const sigset_t * restrict newsigmask);
DESCRIPTION
The pselect() function was introduced by IEEE Std 1003.1g-2000
("POSIX.1g") as a slightly stronger version of select(2). The nfds,
readfds, writefds, and exceptfds arguments are all identical to the
analogous arguments of select(). The timeout argument in pselect()
points to a const struct timespec rather than the potentially modifiable
struct timeval used by select(); as in select(), a null pointer may be
passed to indicate that pselect() should wait indefinitely. Finally,
newsigmask specifies a signal mask which is set while waiting for input.
When pselect() returns, the original signal mask is restored. If
newsigmask is a null pointer, pselect() behaves like select() with no
setting or restoration of the signal mask.
See select(2) for a more detailed discussion of the semantics of this
interface, and for macros used to manipulate the fd_set data type.
RETURN VALUES
The pselect() function returns the same values and under the same
conditions as select().
ERRORS
The pselect() function may fail for any of the reasons documented for
select(2) and (if a signal mask is provided) sigprocmask(2).
SEE ALSO
kqueue(2), poll(2), select(2), sigprocmask(2), sigsuspend(2)
STANDARDS
The pselect() function conforms to IEEE Std 1003.1-2001 ("POSIX.1").
HISTORY
The pselect() function first appeared in FreeBSD 5.0.
AUTHORS
The first implementation of pselect() function and this manual page were
written by Garrett Wollman <wollman@FreeBSD.org>.
FreeBSD 14.2-RELEASE July 2, 2022 FreeBSD 14.2-RELEASE