NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | CONFORMING TO | NOTES | SEE ALSO | COLOPHON

GETDTABLESIZE(2)              Linux Programmer's Manual              GETDTABLESIZE(2)

NAME         top

       getdtablesize - get descriptor table size

SYNOPSIS         top

       #include <unistd.h>

       int getdtablesize(void);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       getdtablesize(): _BSD_SOURCE || _XOPEN_SOURCE >= 500

DESCRIPTION         top

       getdtablesize() returns the maximum number of files a process can have open,
       one more than the largest possible value for a file descriptor.

RETURN VALUE         top

       The current limit on the number of open files per process.

ERRORS         top

       On Linux, getdtablesize() can return any of the errors described for
       getrlimit(2); see NOTES below.

CONFORMING TO         top

       SVr4, 4.4BSD (the getdtablesize() function first appeared in 4.2BSD).  It is
       not specified in POSIX.1-2001; portable applications should employ
       sysconf(_SC_OPEN_MAX) instead of this call.

NOTES         top

       getdtablesize() is implemented as a libc library function.  The glibc version
       calls getrlimit(2) and returns the current RLIMIT_NOFILE limit, or OPEN_MAX
       when that fails.  The libc4 and libc5 versions return OPEN_MAX (set to 256
       since Linux 0.98.4).

SEE ALSO         top

       close(2), dup(2), getrlimit(2), open(2)

COLOPHON         top

       This page is part of release 3.23 of the Linux man-pages project.  A
       description of the project, and information about reporting bugs, can be found
       at http://www.kernel.org/doc/man-pages/.

Linux                                 2007-07-26                     GETDTABLESIZE(2)