sysconf

Runtime system configuration value for the given _SC_* name.

Synopsis

use POSIX qw(sysconf _SC_OPEN_MAX _SC_PAGESIZE);
my $max_fd = sysconf(_SC_OPEN_MAX);

What you get back

The configured value, or -1 if the option is not supported (in which case $! may or may not be set — distinguish by checking $! before and after).

Differences from upstream

Fully compatible with upstream POSIX.