GNU Autoconf, Automake, and Libtool

21.4. Utilities

The utility programs commonly executed by shell scripts can have a huge impact on the portability of shell scripts, and it is important to know which utilities are universally available and any differences certain implementations of these utilities may exhibit. According to the GNU standards document, you can rely on having access to these utilities from your scripts:

cat cmp cp diff echo egrep expr false grep install-info
ln ls mkdir mv pwd rm rmdir sed sleep sort tar test touch true

You must be aware of the following things when using some of these tools:

cat	Host architectures supply cat implementations with conflicting interpretations of, or entirely missing, the various command-line options. You should avoid using any command-line ...