getdtablesize − get descriptor table size

#include <unistd.h>

int getdtablesize(void);

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

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

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).

SVr4, 4.4BSD (the getdtablesize function first appeared in BSD 4.2).

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