diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/sysconf.c')
| -rw-r--r-- | sysdeps/unix/sysv/linux/sysconf.c | 38 |
1 files changed, 36 insertions, 2 deletions
diff --git a/sysdeps/unix/sysv/linux/sysconf.c b/sysdeps/unix/sysv/linux/sysconf.c index e07c502cc3..842c8794d0 100644 --- a/sysdeps/unix/sysv/linux/sysconf.c +++ b/sysdeps/unix/sysv/linux/sysconf.c @@ -1,5 +1,5 @@ /* Get file-specific information about a file. Linux version. - Copyright (C) 2003 Free Software Foundation, Inc. + Copyright (C) 2003, 2004 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or @@ -17,6 +17,7 @@ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. */ +#include <fcntl.h> #include <sysdep.h> #include <time.h> #include <unistd.h> @@ -46,7 +47,40 @@ __sysconf (int name) } #endif + case _SC_NGROUPS_MAX: + { + /* Try to read the information from the /proc/sys/kernel/ngroups_max + file. */ + int fd = __open ("/proc/sys/kernel/ngroups_max", O_RDONLY); + if (fd != -1) + { + /* This is more than enough, the file contains a single + integer. */ + char buf[32]; + long int res = -1l; + + ssize_t n = __read (fd, buf, sizeof (buf) - 1); + if (n > 0) + { + /* Terminate the string. */ + buf[n] = '\0'; + + char *endp; + res = strtol (buf, &endp, 10); + if (endp == buf || (*endp != '\0' && *endp != '\n')) + res = -1l; + } + + __close (fd); + + if (res != -1) + return res; + } + } + break; + default: - return posix_sysconf (name); + break; } + return posix_sysconf (name); } |