Linux tips series

To replace the last command with the same arguments

commandName !*  - for all arguments

commandName !$  - for the last argument

commandName !:N - for the Nth argument

Using grep recursively

grep -r "text_to_grep" .

grep -r --include "*.txt" "text_to_grep" .
grep --include="*.csv" -nRHI "text_to_grep" *


After compiling a code, you may search for the executable (if you have a number of files in that directory). In this case, you can use ls -ltr to list all the files as per the time they are created. For example, see blwo.

gfortran -o code.out code.f90

If you run above line you will get the executable code.out in the same directory. But to look at this file, you can type,

ls -ltr

This will list all the files with code.out at the end of the list. This is a quick check for checking whether the executable is created or not. This will be useful when you teach or create a tutorial on coding.


Use top command to check which jobs are running.
Suppose you submit a job to compute in Linux. If you are not sure whether the job is completed or not, use 'top' command to check.

Type on the terminal
top

Now, you will get list of jobs running on the computer.
Then press 1 to see the latest jobs on top.