Difference between revisions of "Awk"
From Linuxintro
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* Show only the second column of ''file.txt'' | * Show only the second column of ''file.txt'' | ||
awk '{print $2;}' ''file.txt'' | awk '{print $2;}' ''file.txt'' | ||
| − | * kill all processes of a user | + | * kill all processes of a user ''username'' |
| − | [[ps]] --no-header -fu | + | [[ps]] --no-header -fu ''username'' | [[awk]] '{ print $2 }' | [[grep]] -v $$ | [[xargs]] kill |
* extract ''eth0'''s MAC address from ifconfig output | * extract ''eth0'''s MAC address from ifconfig output | ||
ifconfig | grep ''eth0'' | awk '{ print $5 }' | ifconfig | grep ''eth0'' | awk '{ print $5 }' | ||
Revision as of 07:09, 27 September 2013
awk is a command for string operations. For example, it allows you to show only the second column of a file. awk and gawk (for GNU awk) are used synonymously.
- Examples
- Show only the second column of file.txt
awk '{print $2;}' file.txt
- kill all processes of a user username
ps --no-header -fu username | awk '{ print $2 }' | grep -v $$ | xargs kill
- extract eth0's MAC address from ifconfig output
ifconfig | grep eth0 | awk '{ print $5 }'
- sorted list of memory consumption by applications
# ps aux|awk '{print $6" " $11;s=s+$6} END {print s}' | sort -n
The output will look like this:
[...] 4028 dovecot/auth 4528 /sbin/haveged 8348 /usr/sbin/httpd2-prefork 38764 /usr/sbin/httpd2-prefork 43628 /usr/sbin/httpd2-prefork 279148
