Unix Specific Services
The modules described in this chapter provide interfaces to features that are unique to the Unix operating system, or in some cases to some or many variants of it. Here’s an overview:
posix— The most common POSIX system callspwd— The password databasespwd— The shadow password databasegrp— The group databasecrypt— Function to check Unix passwordstermios— POSIX style tty controltty— Terminal control functionspty— Pseudo-terminal utilitiesfcntl— Thefcntlandioctlsystem callspipes— Interface to shell pipelinesresource— Resource usage informationnis— Interface to Sun’s NIS (Yellow Pages)syslog— Unix syslog library routines