UNIX commands
R. Checa-Garcia (CC BY-NC-SA) COMPUTING-BLOG
Scientific Computing Linux Unix
Tips
Table of Contents
This post collects a list of shorts tips related with UNIX terminal tools. To extract information of a file, to find specific archives, etc …
awk and pr
AWK (or gawk) is a quite powerful line command. This is an example of how to combine it with pr. The pr command is useful to, for example, create a file with two columns from two previous one column files (or more complex operations).
The next example is based on a very simple file test-file.data 1 house hause
b 2 day tag
h 7 cinema kino
u 23 chess schach
You can simply try!cp test-file.dat del_later
gawk '{print $1 }' del_later > COL1; more COL1
gawk '{print $2 }' del_later > COL2; more COL2
gawk '{print $3 }' del_later > COL3; more COL3
gawk '{print $2, $NF }' del_later > COL2_last; more COL2_last
gawk '{print $3, $NF }' del_later > COL3_last; more COL3_last
pr -m -t -s\ COL2_last COL3_last
cut
cut may be used to select an specific column numbercut -f
cut -c 129 file.txt > new_file.txt
Soft filelinks
ln -s orginal_filename newsoftlink_filename
jobs
Gives a list of those processes in background in the current shell sessionjobs
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