I want to retrieve the second column from ps result:
test@pc:~$ ps -e | head -5 | cut -d '' -f1 PID TTY TIME CMD 1 ? 00:00:03 systemd 2 ? 00:00:00 kthreadd 3 ? 00:00:00 rcu_gp 4 ? 00:00:00 rcu_par_gpIt does not work, I learned that it could be solve the a complicated way as:
test@pc:~$ ps -e | head -5 | gawk '{print $2}'
TTY
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?How could solve the problem with the generic tool of cut?
1 Answer
First we replace each sequence of a repeated spaces using tr -s ' ' then we grab the 3th column:
ps -e | head -5 | tr -s ' ' | cut -d ' ' -f33th column because there is a space at the beginning of each line. We can remove that too:
ps -e | head -5 | tr -s ' ' | sed 's/ //' | cut -d ' ' -f2
