PSELECT(3) BSD Library Functions Manual PSELECT(3)NAMEpselect — synchronous I/O multiplexing a la POSIX.1g
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <unistd.h>
int
pselect(int nfds, fd_set *restrict readfds, fd_set *restrict writefds,
fd_set *restrict errorfds, const struct timespec *restrict timeout,
const sigset_t *restrict sigmask);
DESCRIPTION
The pselect() function was introduced by IEEE Std 1003.1g-2000
(“POSIX.1”) as a slightly stronger version of select(2). The nfds,
readfds, writefds, and errorfds arguments are all identical to the analo‐
gous arguments of select(). The timeout argument in pselect() points to
a const struct timespec, rather than the (modifiable) struct timeval used
by select(); as in select(), a null pointer may be passed to indicate
that pselect() should wait indefinitely. Finally, sigmask specifies a
signal mask which is set while waiting for input. When pselect()
returns, the original signal mask is restored.
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.
IMPLEMENTATION NOTES
The pselect() function is implemented in the C library as a wrapper
around select().
RETURN VALUES
The pselect() function returns the same values and under the same condi‐
tions 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 ALSOkqueue(2), poll(2), select(2), sigprocmask(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 pselect() function and this manual page were written by Garrett
Wollman ⟨wollman@FreeBSD.org⟩.
BSD June 16, 2002 BSD
