getdtablesize2
Get file descriptor table size
Part of getdtablesize(3).
Usage
#include <unistd.h>
int getdtablesize(void);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
getdtablesize():
- Since glibc 2.12:
-
/* Glibc since 2.19: */ _DEFAULT_SOURCE || /* Glibc versions <= 2.19: */ _BSD_SOURCE || ! (_POSIX_C_SOURCE >= 200112L)
- Before glibc 2.12:
-
_BSD_SOURCE || _XOPEN_SOURCE >= 500
Overview
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
The current limit on the number of open files per process.
Errors
On Linux, getdtablesize() can return any of the errors described for getrlimit(2); see NOTES below.
Attributes
For an explanation of the terms used in this section, see attributes(7).
| Interface | Attribute | Value |
| getdtablesize() | Thread safety | MT-Safe |
Notes
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.
Releases
15 releases since Debian 1.1 (Buzz); the text changed 11 times.