Table of Contents

atexit - evaluates code before exiting a program.
block_signal, unblock_signal - delimit signal blocking.
errno - detects and numbers errors.
exec - executes a program.
exit_program - terminates the interpreter.
fork - duplicates a process.
getenv - retrieves the value of an environment variable.
gethostname - gets the computer's host name.
getnid - returns the local node number.
getpid - returns the program ID.
getsockopt, setsockopt - get and set a socket option.
kill - sends a signal to a process.
nanosleep - pauses the interpreter for seconds and nanoseconds.
setenv - sets an environment variable for the current process.
shm_open - opens shared memory objects.
shm_unlink - removes shared memory objects.
signal - defines an expression to be evaluated at an OS generated signal.
sleep, usleep - suspend execution.
strerror - retrieves an error message.
system - treats its argument as a system command.
tcp_accept - forks a new TCP socket on the server side to accept a new connection.
tcp_connect - creates a client-side TCP socket connection.
tcp_listen - creates a server-side TCP socket connection.
wait - waits for process exit status.