The following commands, or symbolic links to commands, are required in /bin.
cat | Utility to concatenate files to standard output |
chgrp | Utility to change file group ownership |
chmod | Utility to change file access permissions |
chown | Utility to change file owner and group |
cp | Utility to copy files and directories |
date | Utility to print or set the system data and time |
dd | Utility to convert and copy a file |
df | Utility to report filesystem disk space usage |
dmesg | Utility to print or control the kernel message buffer |
echo | Utility to display a line of text |
false | Utility to do nothing, unsuccessfully |
hostname | Utility to show or set the system's host name |
kill | Utility to send signals to processes |
ln | Utility to make links between files |
login | Utility to begin a session on the system |
ls | Utility to list directory contents |
mkdir | Utility to make directories |
mknod | Utility to make block or character special files |
more | Utility to page through text |
mount | Utility to mount a filesystem |
mv | Utility to move/rename files |
ps | Utility to report process status |
pwd | Utility to print name of current working directory |
rm | Utility to remove files or directories |
rmdir | Utility to remove empty directories |
sed | The `sed' stream editor |
sh | The Bourne command shell |
stty | Utility to change and print terminal line settings |
su | Utility to change user ID |
sync | Utility to flush filesystem buffers |
true | Utility to do nothing, successfully |
umount | Utility to unmount file systems |
uname | Utility to print system information |
Table 3.4.2.1
If /bin/sh is not a true Bourne shell, it must be a hard or symbolic link to the real shell command.
The [ and test commands must be placed together in either /bin or /usr/bin.
The requirement for the [ and test commands to be
included as binaries (even if implemented internally by the shell) is shared with the POSIX.2 standard.
csh | The C shell (optional) |
ed | The `ed' editor (optional) |
tar | The tar archiving utility (optional) |
cpio | The cpio archiving utility (optional) |
gzip | The GNU compression utility (optional) |
gunzip | The GNU uncompression utility (optional) |
zcat | The GNU uncompression utility (optional) |
netstat | The network statistics utility (optional) |
ping | The ICMP network test utility (optional) |
Table 3.4.3.2
If the gunzip and zcat programs exist, they must be symbolic or hard links to gzip. /bin/csh may be a symbolic link to /bin/tcsh or /usr/bin/tcsh.
Conversely, if no restoration from the root partition is ever expected,
then these binaries might be omitted (e.g., a ROM chip root, mounting
/usr through NFS). If restoration of a system is planned
through the network, then ftp or tftp (along with
everything necessary to get an ftp connection) must be available on
the root partition.
[1] Command binaries that are not essential enough to place into /bin must be placed in /usr/bin, instead. Items that are required only by non-root users (the X Window System, chsh, etc.) are generally not essential enough to be placed into the root partition.