LDP: Update original to LDP v3.79

[linuxjm/LDP_man-pages.git] / original / man2 / poll.2

diff --git a/original/man2/poll.2 b/original/man2/poll.2
index f034001..1e7c0b2 100644 (file)
--- a/original/man2/poll.2
+++ b/original/man2/poll.2
@@ -28,7 +28,7 @@
 .\" 2006-07-01, mtk, Added POLLRDHUP + various other wording and
 .\"    formatting changes.
 .\"
-.TH POLL 2 2014-01-31 "Linux" "Linux Programmer's Manual"
+.TH POLL 2 2014-09-06 "Linux" "Linux Programmer's Manual"
 .SH NAME
 poll, ppoll \- wait for some event on a file descriptor
 .SH SYNOPSIS
@@ -38,6 +38,7 @@ poll, ppoll \- wait for some event on a file descriptor
 .BI "int poll(struct pollfd *" fds ", nfds_t " nfds ", int " timeout );
 .sp
 .BR "#define _GNU_SOURCE" "         /* See feature_test_macros(7) */"
+.B #include <signal.h>
 .B #include <poll.h>
 .sp
 .BI "int ppoll(struct pollfd *" fds ", nfds_t " nfds ", "
@@ -82,7 +83,8 @@ file descriptor for a single
 .BR poll ()
 call: simply negate the
 .I fd
-field.)
+field.
+Note, however, that this technique can't be used to ignore file descriptor 0.)
 
 The field
 .I events
@@ -165,7 +167,10 @@ There is urgent data to read (e.g., out-of-band data on TCP socket;
 pseudoterminal master in packet mode has seen state change in slave).
 .TP
 .B POLLOUT
-Writing now will not block.
+Writing is now possible, though a write larger that the available space
+in a socket or pipe will still block (unless
+.B O_NONBLOCK
+is set).
 .TP
 .BR POLLRDHUP " (since Linux 2.6.17)"
 Stream socket peer closed connection,
@@ -358,7 +363,7 @@ For a discussion of what may happen if a file descriptor being monitored by
 .BR poll ()
 is closed in another thread, see
 .BR select (2).
-.SS Linux notes
+.SS C library/kernel ABI differences
 The Linux
 .BR ppoll ()
 system call modifies its
@@ -372,6 +377,19 @@ Thus, the glibc
 function does not modify its
 .I timeout_ts
 argument.
+
+The raw
+.BR ppoll ()
+system call has a fifth argument,
+.IR "size_t sigsetsize" ,
+which specifies the size in bytes of the
+.IR sigmask
+argument.
+The glibc
+.BR ppoll ()
+wrapper function specifies this argument as a fixed value
+(equal to
+.IR sizeof(sigset_t) ).
 .SH BUGS
 See the discussion of spurious readiness notifications under the
 BUGS section of
@@ -381,3 +399,12 @@ BUGS section of
 .BR select (2),
 .BR select_tut (2),
 .BR time (7)
+.SH COLOPHON
+This page is part of release 3.79 of the Linux
+.I man-pages
+project.
+A description of the project,
+information about reporting bugs,
+and the latest version of this page,
+can be found at
+\%http://www.kernel.org/doc/man\-pages/.