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PSELECT(3)		     Library Functions Manual		      PSELECT(3)

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.1")
     as a slightly stronger version of select(2).  The nfds, readfds,  writefds,
     and exceptfds arguments are all identical to the analogous arguments of se-
     lect().   The  timeout argument in pselect() points to a const struct time-
     spec 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, newsigmask 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  in-
     terface, 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 se-
     lect(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>.

FreeBSD 5.0			  June 16, 2002 		      PSELECT(3)
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