getdtablesize(3) Library Functions Manual getdtablesize(3) getdtablesize - (libc -lc) #include int getdtablesize(void); glibc ( feature_test_macros(7)): getdtablesize(): glibc 2.20: _DEFAULT_SOURCE || ! (_POSIX_C_SOURCE >= 200112L) glibc 2.12 glibc 2.19: _BSD_SOURCE || ! (_POSIX_C_SOURCE >= 200112L) glibc 2.12: _BSD_SOURCE || _XOPEN_SOURCE >= 500 getdtablesize() . . getdtablesize() getrlimit(2); . attributes(7). +------------+------------------------------------+--------------------+ || | | +------------+------------------------------------+--------------------+ |getdtablesize()| | MT-Safe | | | | | +------------+------------------------------------+--------------------+ glibc getdtablesize() getrlimit(2) RLIMIT_NOFILE OPEN_MAX . sysconf(_SC_OPEN_MAX) . . SVr4, 4.4BSD ( 4.2BSD). close(2), dup(2), getrlimit(2), open(2) 3 . . : . 6.18 8 2026 getdtablesize(3)