From 6b6e9185500079f2aacfb0925507b92aed3b368b Mon Sep 17 00:00:00 2001 From: Nikos Mavrogiannopoulos Date: Fri, 29 Jan 2016 10:08:52 +0100 Subject: [PATCH] select.2: Mention the 'fd_set' size limitation early and refer to poll(2) Change this because of the serious limitation of select() imposing a limit on the range of file descriptors that can be monitored. This is currently mentioned too late in the documentation (in the NOTES section). The man page should warn early and refer to poll(2) as soon as possible. Signed-off-by: Nikos Mavrogiannopoulos Signed-off-by: Michael Kerrisk --- man2/select.2 | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/man2/select.2 b/man2/select.2 index 151932eaf..6c76e1c7d 100644 --- a/man2/select.2 +++ b/man2/select.2 @@ -91,6 +91,13 @@ perform a corresponding I/O operation (e.g., without blocking, or a sufficiently small .BR write (2)). .PP +The file descriptors +.BR select () +can monitor cannot be larger than +.B FD_SETSIZE. +.BR poll (2), +does not have this limitation. +.PP The operation of .BR select () and