This is a handy one liner that searches and replaces text in multiple files. (You can use find for example to run it in multiple folders) View Code BASH1 perl -pi -e 's/old_text/new_text/g' *.conf This line replaces old_text with new_text in all the .conf files in the current folder. Of course you can use...
Bash scripting
Quickly check if a process is running or not
When writting bash scripts one often needs to see if a process is running or not I like the following code; though I’m sure many ways of doing this exists, what’s your favorite? View Code BASH1 2 3 4 5 6 if [ -z "$(pgrep process)" ] then echo "process is not running" else...
Optimizing all mysql tables (from all databases)
You want to optimize mysql tables from time to time in order to reduce fragmentation. Here’s an easy way to do it automatically (put it in a script and run it from cron for example) View Code BASH1 mysqlcheck -Aop -h hostname -u user -pPASSWORD What all those mean: –all-databases, -A; Check all tables...
List crontab entries for all users on a linux system
This is a good one liner to remember: for user in $(cut -f1 -d: /etc/passwd); do crontab -u $user -l; done
Force fsck on next reboot
Let’s say you run a headless server and you want to fsck the main partition. The easy solution in this case is (if possible) to force fsck to run on the next boot. If you run slackware than all you really need is to create an empty file in /etc called forcefsck You could...
Wma to Mp3 a folder in one command line
I have some albums that were ripped in wma form (yes a shame I know). I wanted them converted into mp3 so my collection remains consistent. So this would be a command to run in a folder filled with .wma files. This keeps the names but not the tags so be sure to use...
Rename all files in a folder from upper to lower case.
Sometimes is needed to have all files in a folder in the same case. Here’s a small script to rename all files in the folder to lower case: View Code BASH1 for i in *; do mv $i `echo $i | tr [:upper:] [:lower:]`; done
Export a MySQL database using the command line.
Sometimes it’s easier to just drop to the command line then browse for fancy tools like phpMyAdmin. This is useful, especially for quick jobs. View Code BASH1 mysqldump -u user -ppassword your_database > database_backup.sql Of course you need to replace: user – mysql username password – the password your_database – the database you want...
Checking directory sizes from the BASH prompt
The command ls can be made to show directories and permission but it will not display directory sizes. Then it’s time for other commands. For example on my hosting account there is no file manager installed and evidently x and kde is missing too so, to find out directory sizes I can use the...
Follow Me
Recent Comments