Some shell script programmers use absolute paths for even common system tools:
/bin/sed '/^$/d' data
This command line is intended to print the contents of the data file, but to skip blank lines. It does work on most GNU/Linux systems, but why specify the full /bin/sed path? Why not just sed?
Worse, sometimes people try to abbreviate this by saving the full paths in variables, after retrieving them with a non-standard tool such as which:
# Terrible code; never do this! SED=$(which sed) $SED '/^$d/' data
Can you see anything else wrong with this code? Hint: what was the very first thing we re-emphasized in this chapter?
This use of which and full paths such as this is unnecessary, and there are no advantages to ...
