| signal (Distributable) |
| sigpending (Distributable) |
| sigprocmask (Distributable) |
| sigqueue (Distributable) |
| sigreturn (Distributable) |
| sigsuspend (Distributable) |
| sigtimedwait (Distributable) |
| sigwaitinfo (Distributable) |
| socket (BSD/Adv/UCB) |
| socketcall (GPL) |
| socketpair (BSD/Adv/UCB) |
| splice (Distributable) |
| ssetmask (Distributable) |
| stat (Distributable) |
| statfs (Distributable) |
| statvfs (Distributable) |
| stime (Distributable) |
| stty (GPL) |
| swapoff (Distributable) |
| swapon (Distributable) |
| symlink (Distributable) |
| symlinkat (Distributable) |
| sync (Distributable) |
| sync_file_range (Distributable) |
| syscall (BSD/Adv/UCB) |
| syscalls (Distributable) |
| sysctl (Distributable) |
| sysfs (Distributable) |
| sysinfo (Distributable) |
| syslog (Distributable) |
| tee (Distributable) |
| tgkill (Distributable) |
| time (Distributable) |
| times (Distributable) |
| tkill (Distributable) |
| truncate (BSD/Adv/UCB) |
| ugetrlimit (Public Domain) |
| ulimit (GPL) |
| umask (Distributable) |
| umount (Distributable) |
| umount2 (Distributable) |
| uname (Distributable) |
| undocumented (Public Domain) |
| unimplemented (GPL) |
| unlink (Distributable) |
| unlinkat (Distributable) |
| unshare (GPL) |
| uselib (Distributable) |
| ustat (Distributable) |
| utime (Distributable) |
| utimes (Distributable) |
| vfork (Distributable) |
| vhangup (Distributable) |
| vm86 (Distributable) |
| vm86old (Distributable) |
| vmsplice (Distributable) |
| wait (Distributable) |
| wait3 (Distributable) |
| wait4 (Distributable) |
| waitid (Distributable) |
| waitpid (Distributable) |
| write (Distributable) |
| writev (Distributable) |