• fork -- create a new process
  • wait, wait3, wait4, waitpid -- wait for process termination
  • signal -- simplified software signal facilities
  • kill
  • exit
  • getenv
  • getcwd
  • chdir
  • stat
  • lstat
  • fstat
  • execve
  • dup
  • dup2
  • pipe
  • opendir
  • readdir
  • closedir
  • strerror