Bug #69637 [Com]: stream_select() warns: recompile php with FD_SETSIZE>1024 but it already is

Edit report at https://bugs.php.net/bug.php?id=69637&edit=1 ID: 69637 Comment by: erw at macrovita dot com dot br Reported by: bousset1 at gmail dot com Summary: stream_select() warns: recompile php with FD_SETSIZE>1024 but it already is Status: Verified Type: Bug Package: Sockets related Operating System: linux (tested on ubuntu 14.04) PHP Version: 5.6.8 Block user comment: N Private report: N New Comment: If PHP process has more open file descriptors than FD_SETSIZE, it seems stream_select() will fail even when trying to monitor just a couple file descriptors. I get the error even when trying to stream_select() only 2 file descriptors, apparently because the apache process has thousands of file descriptors open. Environment: apache-2.4.23 event mpm, php-7.0.11, Gentoo Linux // BTM11121, BTM10159 Previous Comments: ------------------------------------------------------------------------ [2016-11-08 10:45:07] kexianbin at diyism dot com 1.vi /usr/include/x86_64-linux-gnu/bits/typesizes.h: #define __FD_SETSIZE 65536 2.compile: ./configure --with-curl --enable-fd-setsize=65536 CFLAGS='-D_FORTIFY_SOURCE=0' make && sudo make install 3.vi /etc/security/limits.conf: * soft nofile 65535 * hard nofile 65535 ------------------------------------------------------------------------ [2016-07-03 12:30:29] cmb@php.net Related To: Bug #43269 ------------------------------------------------------------------------ [2016-07-02 15:20:57] cmb@php.net Related To: Bug #72030 ------------------------------------------------------------------------ [2016-05-31 21:05:34] deriamis at gmail dot com The reason this appears to be happening is that sys/select.h on Linux is overriding FD_SETSIZE by setting it to the value of __FD_SETSIZE, which is set statically to 1024, without checking that it's already defined. The --enable-fd-setsize is not cross-platform and, people who need this either have to patch PHP source in several places (bad) or system include files (worse). I think a good way to do this is to set a dummy value and then in source set both FD_SETSIZE and __FD_SETSIZE to the dummy value immediately before the sys/select.h include. ------------------------------------------------------------------------ [2015-08-27 23:57:01] cmb@php.net After changing the definition of __FD_SETSIZE in bits/typesizes.h the script runs fine for me (Debian Jessie) without warning, except for the spurious "weird crash" error message. Did you recompile *everything* after changing __FD_SETSIZE? And of course, check whether FD_SETSIZE really changed. Anyhow, I consider it a bug that --enable-fd-setsize might not have any effect, without producing at least a meaningful warning message. A respective check in configure.in would be appropriate. ------------------------------------------------------------------------ The remainder of the comments for this report are too long. To view the rest of the comments, please view the bug report online at https://bugs.php.net/bug.php?id=69637 -- Edit this bug report at https://bugs.php.net/bug.php?id=69637&edit=1