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Alternatives to busybox commands

Unlike previous releases of Red Hat Enterprise Linux, Red Hat Enterprise Linux 6 does not include a version of busybox to provide shell commands in the pre-installation and post-installation environments. Table G.1, “Alternatives to busybox commands” contains a list of busybox commands, equivalent ways to implement the same functionality in bash, and the availability of these alternatives in the %pre and %post environments. The table also indicates the exact path to the command, although you do not generally need to specify the path because the PATH environment variable is set in the installation environment.

If a command is only available in %post, the command is running on the target system and its availability therefore depends on whether the package that provides the command is installed. Every command that appears in the "New command or alternative" column of Table G.1, “Alternatives to busybox commands” is available for Red Hat Enterprise Linux 6, although not every command is available on every installed system.

Where a command is listed as unavailable, you might be able to create equivalent functionality with a Python script. The Python language is available to %pre and %post script authors, complete with a set of Python modules ready for use. Therefore, if a particular command is not available to you in the installation environment, we recommend that you use Python as the script language.

Table G.1. Alternatives to busybox commands

Busybox command	`%pre`	`%post`	New command or alternative
`addgroup`	no	yes	`/usr/sbin/groupadd`
`adduser`	no	yes	`/usr/sbin/useradd`
`adjtimex`	no	no	none
`ar`	no	yes	`/usr/bin/ar`
`arping`	yes	yes	`/sbin/arping` or `/usr/sbin/arping`
`ash`	yes	yes	`/bin/bash`
`awk`	yes	yes	`/sbin/awk`, `/sbin/gawk`, or `/usr/bin/gawk` ^[a]
`basename`	yes	yes	`/bin/bash` ^[b], `/usr/bin/basename`
`bbconfig`	no	no	none — this command is a specific to Busybox
`bunzip2`	yes	yes	`/usr/bin/bunzip2`, `/usr/bin/bzip2 -d`
`busybox`	no	no	none
`bzcat`	yes	yes	`/usr/bin/bzcat`, `/usr/bin/bzip2 -dc`
`cal`	no	yes	`/usr/bin/cal`
`cat`	yes	yes	`/usr/bin/cat`
`catv`	no	no	`cat -vET` or `cat -A`
`chattr`	yes	yes	`/usr/bin/chattr`
`chgrp`	yes	yes	`/usr/bin/chgrp`
`chmod`	yes	yes	`/usr/bin/chmod`
`chown`	yes	yes	`/usr/bin/chown`
`chroot`	yes	yes	`/usr/sbin/chroot`
`chvt`	yes	yes	`/usr/bin/chvt`
`cksum`	no	yes	`/usr/bin/cksum`
`clear`	yes	yes	`/usr/bin/clear`
`cmp`	no	yes	`/usr/bin/cmp`
`comm`	no	yes	`/usr/bin/comm`
`cp`	yes	yes	`/usr/bin/cp`
`cpio`	yes	yes	`/usr/bin/cpio`
`crond`	no	no	none — no daemons available to scriptlets
`crontab`	no	yes	`/usr/bin/crontab`
`cut`	yes	yes	`/usr/bin/cut`
`date`	yes	yes	`/usr/bin/date`
`dc`	no	yes	`/usr/bin/dc`
`dd`	yes	yes	`/usr/bin/dd`
`deallocvt`	no	yes	`/usr/bin/deallocvt`
`delgroup`	no	yes	`/usr/sbin/groupdel`
`deluser`	no	yes	`/usr/sbin/userdel`
`devfsd`	no	no	none — Red Hat Enterprise Linux does not use devfs
`df`	yes	yes	`/usr/bin/df`
`diff`	no	yes	`/usr/bin/diff`
`dirname`	yes	yes	`/bin/bash` ^[c], `/usr/bin/dirname`
`dmesg`	yes	yes	`/usr/bin/dmesg`
`dnsd`	no	no	none — no daemons available to scriptlets
`dos2unix`	no	no	`sed 's/.$//'`
`dpkg`	no	no	none — no support for Debian packages
`dpkg-deb`	no	no	none — no support for Debian packages
`du`	yes	yes	`/usr/bin/du`
`dumpkmap`	no	no	none
`dumpleases`	no	no	none
`e2fsck`	yes	yes	`/usr/sbin/e2fsck`
`e2label`	yes	yes	`/usr/sbin/e2label`
`echo`	yes	yes	`/usr/bin/echo`
`ed`	no	no	`/sbin/sed`, `/usr/bin/sed`
`egrep`	yes	yes	`/sbin/egrep`, `/usr/bin/egrep`
`eject`	yes	yes	`/usr/bin/eject`
`env`	yes	yes	`/usr/bin/env`
`ether-wake`	no	no	none
`expr`	yes	yes	`/usr/bin/expr`
`fakeidentd`	no	no	none — no daemons available to scriptlets
`false`	yes	yes	`/usr/bin/false`
`fbset`	no	yes	`/usr/sbin/fbset`
`fdflush`	no	no	none
`fdformat`	no	yes	`/usr/bin/fdformat`
`fdisk`	yes	yes	`/usr/sbin/fdisk`
`fgrep`	yes	yes	`/sbin/fgrep`, `/usr/bin/fgrep`
`find`	yes	yes	`/usr/bin/find`
`findfs`	no	no	none
`fold`	no	yes	`/usr/bin/fold`
`free`	no	yes	`/usr/bin/free`
`freeramdisk`	no	no	none
`fsck`	yes	yes	`/usr/sbin/fsck`
`fsck.ext2`	yes	yes	`/usr/sbin/fsck.ext2`, `/usr/sbin/e2fsck`
`fsck.ext3`	yes	yes	`/usr/sbin/fsck.ext3`, `/usr/sbin/e2fsck`
`fsck.minix`	no	no	none — no support for the Minix file system
`ftpget`	yes	yes	`/usr/bin/ftp` or Python ftplib module
`ftpput`	yes	yes	`/usr/bin/ftp` or Python ftplib module
`fuser`	no	yes	`/sbin/fuser`
`getopt`	no	yes	`/usr/bin/getopt`
`getty`	no	no	none
`grep`	yes	yes	`/sbin/grep`, `/usr/bin/grep`
`gunzip`	yes	yes	`/usr/bin/gunzip`, `/usr/bin/gzip -d`
`gzip`	yes	yes	`/usr/bin/gzip`
`hdparm`	yes	yes	`/usr/sbin/hdparm`
`head`	yes	yes	`/usr/bin/head`
`hexdump`	no	yes	`/usr/bin/hexdump`
`hostid`	no	yes	`/usr/bin/hostid or Python`
`hostname`	yes	yes	`/sbin/hostname`, `/usr/bin/hostname`
`httpd`	no	no	none — no daemons available to scriptlets
`hush`	no	no	none
`hwclock`	yes	yes	`/usr/sbin/hwclock`
`id`	no	yes	`/usr/bin/id` or Python
`ifconfig`	yes	yes	`/sbin/ifconfig`, `/usr/sbin/ifconfig`
`ifdown`	no	no	`ifconfig device down`
`ifup`	no	no	`ifconfig device up`
`inetd`	no	no	none — no daemons available to scriptlets
`insmod`	yes	yes	`/sbin/insmod`, `/usr/sbin/insmod`
`install`	no	yes	`/usr/bin/install or mkdir/cp/chmod/chown/chgrp`
`ip`	yes	yes	`/sbin/ip`, `/usr/sbin/ip`
`ipaddr`	no	no	`ifconfig` or `ip`
`ipcalc`	yes	yes	`/sbin/ipcalc`, `/usr/bin/ipcalc`
`ipcrm`	no	yes	`/usr/bin/ipcrm`
`ipcs`	no	yes	`/usr/bin/ipcs`
`iplink`	no	no	`ip`
`iproute`	no	no	`ip`
`iptunnel`	no	yes	`/sbin/iptunnel`
`kill`	yes	yes	`/sbin/kill`, `/usr/bin/kill`
`killall`	yes	yes	`/usr/bin/killall`
`lash`	no	no	none
`last`	no	yes	`/usr/bin/last`
`length`	no	no	Python or bash
`less`	yes	yes	`/usr/bin/less`
`linux32`	no	no	none
`linux64`	no	no	none
`ln`	yes	yes	`/sbin/ln`, `/usr/bin/ln`
`load_policy`	yes	yes	`/sbin/load_policy`, `/usr/sbin/load_policy`
`loadfont`	no	no	none
`loadkmap`	no	no	none
`login`	yes	yes	`/usr/bin/login`
`logname`	no	yes	`/usr/bin/logname`
`losetup`	yes	yes	`/usr/bin/losetup`
`ls`	yes	yes	`/usr/bin/ls`
`lsattr`	yes	yes	`/usr/bin/lsattr`
`lsmod`	yes	yes	`/usr/bin/lsmod`
`lzmacat`	no	yes	`/usr/bin/lzmadec`
`makedevs`	no	no	`/usr/bin/mknod`
`md5sum`	yes	yes	`/usr/bin/md5sum`
`mdev`	no	no	none
`mesg`	no	yes	`/usr/bin/mesg`
`mkdir`	yes	yes	`/sbin/mkdir`, `/usr/bin/mkdir`
`mke2fs`	yes	yes	`/usr/sbin/mke2fs`
`mkfifo`	no	yes	`/usr/bin/mkfifo`
`mkfs.ext2`	yes	yes	`/usr/sbin/mkfs.ext2`
`mkfs.ext3`	yes	yes	`/usr/sbin/mkfs.ext3`
`mkfs.minix`	no	no	none — no support for Minix filesystem
`mknod`	yes	yes	`/usr/bin/mknod`
`mkswap`	yes	yes	`/usr/sbin/mkswap`
`mktemp`	yes	yes	`/usr/bin/mktemp`
`modprobe`	yes	yes	`/sbin/modprobe`, `/usr/sbin/modprobe`
`more`	yes	yes	`/usr/bin/more`
`mount`	yes	yes	`/sbin/mount`, `/usr/bin/mount`
`mountpoint`	no	no	Look at the output of the mount command
`msh`	no	no	none
`mt`	yes	yes	`/usr/bin/mt`
`mv`	yes	yes	`/usr/bin/mv`
`nameif`	no	no	none
`nc`	no	yes	`/usr/bin/nc`
`netstat`	no	yes	`/bin/netstat`
`nice`	no	yes	`/bin/nice`
`nohup`	no	yes	`/usr/bin/nohup`
`nslookup`	yes	yes	`/usr/bin/nslookup`
`od`	no	yes	`/usr/bin/od`
`openvt`	yes	yes	`/usr/bin/openvt`
`passwd`	no	yes	`/usr/bin/passwd`
`patch`	no	yes	`/usr/bin/patch`
`pidof`	yes	yes	`/usr/sbin/pidof`
`ping`	yes	yes	`/usr/bin/ping`
`ping6`	no	yes	`/bin/ping6`
`pipe_progress`	no	no	none
`pivot_root`	no	yes	`/sbin/pivot_root`
`printenv`	no	yes	`/usr/bin/printenv`
`printf`	no	yes	`/usr/bin/printf`
`ps`	yes	yes	`/usr/bin/ps`
`pwd`	yes	yes	`/usr/bin/pwd`
`rdate`	no	yes	`/usr/bin/rdate`
`readlink`	yes	yes	`/sbin/readlink`, `/usr/bin/readlink`
`readprofile`	no	yes	`/usr/sbin/readprofile`
`realpath`	no	no	Python `os.path.realpath()`
`renice`	no	yes	`/usr/bin/renice`
`reset`	no	yes	`/usr/bin/reset`
`rm`	yes	yes	`/sbin/rm`, `/usr/bin/rm`
`rmdir`	yes	yes	`/sbin/rmdir`, `/usr/bin/rmdir`
`rmmod`	yes	yes	`/sbin/rmmod`, `/usr/bin/rmmod`
`route`	yes	yes	`/sbin/route`, `/usr/sbin/route`
`rpm`	yes	yes	`/usr/bin/rpm`
`rpm2cpio`	no	yes	`/usr/bin/rpm2cpio`
`run-parts`	no	no	none
`runlevel`	no	no	none
`rx`	no	no	none
`sed`	yes	yes	`/sbin/sed`, `/usr/bin/sed`
`seq`	no	yes	`/usr/bin/seq`
`setarch`	no	yes	`/usr/bin/setarch`
`setconsole`	no	no	none
`setkeycodes`	no	yes	`/usr/bin/setkeycodes`
`setlogcons`	no	no	none
`setsid`	no	yes	`/usr/bin/setsid`
`sh`	yes	yes	`/sbin/sh`, `/usr/bin/sh`
`sha1sum`	yes	yes	`/usr/bin/sha1sum`
`sleep`	yes	yes	`/sbin/sleep`, `/usr/bin/sleep`
`sort`	yes	yes	`/usr/bin/sort`
`start-stop-daemon`	no	no	none
`stat`	no	yes	`/usr/bin/stat` or Python `os.stat()`
`strings`	no	yes	`/usr/bin/strings`
`stty`	no	yes	`/bin/stty`
`su`	no	yes	`/bin/su`
`sulogin`	no	yes	`/sbin/sulogin`
`sum`	no	yes	`/usr/bin/sum`
`swapoff`	yes	yes	`/usr/sbin/swapoff`
`swapon`	yes	yes	`/usr/sbin/swapon`
`switch_root`	no	yes	`/sbin/switch_root`
`sync`	yes	yes	`/usr/bin/sync`
`sysctl`	no	yes	`/sbin/sysctl`
`tail`	yes	yes	`/usr/bin/tail`
`tar`	yes	yes	`/usr/bin/tar`
`tee`	yes	yes	`/usr/bin/tee`
`telnet`	yes	yes	`/usr/bin/telnet`
`telnetd`	no	no	none — no daemons available to scriptlets
`test`	no	yes	`/usr/bin/test` or `[` in bash
`tftp`	no	yes	`/usr/bin/tftp`
`time`	no	yes	`/usr/bin/time` or Python
`top`	yes	yes	`/usr/bin/top`
`touch`	yes	yes	`/sbin/touch`, `/usr/bin/touch`
`tr`	no	yes	`/usr/bin/tr` or Python
`traceroute`	no	yes	`/bin/traceroute`
`true`	yes	yes	`/usr/bin/true`
`tty`	no	yes	`/usr/bin/tty`
`tune2fs`	yes	yes	`/usr/sbin/tune2fs`
`udhcpc`	no	no	`/sbin/dhclient`
`udhcpd`	no	no	none — no daemons available to scriptlets
`umount`	yes	yes	`/sbin/umount`, `/usr/bin/umount`
`uname`	no	yes	`/bin/uname` or Python `os.uname()`
`uncompress`	no	no	none
`uniq`	yes	yes	`/usr/bin/uniq`
`unix2dos`	no	no	`sed 's/$//'`
`unlzma`	no	yes	`/usr/bin/unlzma`
`unzip`	no	yes	`/usr/bin/unzip`
`uptime`	no	yes	`/usr/bin/uptime` or Python reading `/proc/uptime`
`usleep`	no	yes	`/bin/usleep` or Python
`uudecode`	no	yes	`/usr/bin/uudecode` or Python
`uuencode`	no	yes	`/usr/bin/uuencode` or Python
`vconfig`	yes	yes	`/usr/sbin/vconfig`
`vi`	yes	yes	`/usr/bin/vi`
`vlock`	no	no	none
`watch`	no	yes	`/usr/bin/watch`
`watchdog`	no	no	none
`wc`	yes	yes	`/usr/bin/wc`
`wget`	yes	yes	`/sbin/wget`, `/usr/bin/wget`
`which`	no	yes	`/usr/bin/which`
`who`	no	yes	`/usr/bin/who`
`whoami`	no	yes	`/usr/bin/whoami`
`xargs`	yes	yes	`/usr/bin/xargs`
`yes`	no	yes	`/usr/bin/yes`
`zcat`	yes	yes	`/usr/bin/zcat`
`zcip`	no	no	NetworkManager should take care of this
^[a] Red Hat Enterprise Linux 6 ships with GNU awk rather than the busybox awk in the installation environment. ^[b] GNU bash can provide basename functionality using string manipulation. If `var="/usr/bin/command"`, then `echo ${var##/}` gives `command`. ^[c] GNU bash can provide dirname functionality using string manipulation. If `var="/usr/bin/command"`, then `echo ${var%/}` gives `/usr/bin`.