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PSELECT(3)               BSD Library Functions Manual               PSELECT(3)

NAME
     pselect -- 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
     analogous 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 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)

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