Editing Linux 101 hacks (section)

=='''Hack 43. Use shell script inside PS1 variable'''==


You can also invoke a shell script inside the PS1 variable. In the example below, the ~/bin/totalfilesize.sh, which calculates the total filesize of the current directory, is invoked inside the PS1 variable.


ramesh@dev-db ~> cat ~/bin/totalfilesize.sh


for filesize in $(ls -l . | grep "^-" | awk '{print $5}')


do


let totalsize=$totalsize+$filesize done


echo -n "$totalsize"


ramesh@dev-db ~> export PATH=$PATH:~/bin


ramesh@dev-db ~> '''export PS1="\u@\h'''


'''<nowiki>[\$(totalfilesize.sh) </nowiki>bytes]> "'''


ramesh@dev-db <nowiki>[534 </nowiki>bytes]> cd /etc/mail


ramesh@dev-db <nowiki>[167997 </nowiki>bytes]>


<nowiki>[</nowiki>'''Note''': This executes the totalfilesize.sh to display the total file size of the current directory in the PS1 prompt]