AWK Find field number

[problem]

Ever needed to print out one column with awk, but do not know the field number?

[/problem]

[solution]

Here I’m running df and looking for a field with “Used” in it:

 df -k | head -1 | awk ' {       for(i=1; i< NF;i++) {          if($i ~ /Used/) {              print "# field "i          }       } } ' 

So stop counting columns and just use the code! 🙂

[/solution]

[example]

Now for a real life demo. 😉


[marcus@bree marcus]$ df -k | head -1
Filesystem 1K-blocks Used Available Use% Mounted on
[marcus@bree marcus]$ df -k | awk ' {
for(i=1;i < NF;i++) {
if($i ~ /Used/) { print "# field "i }
}
} '
# field 3


[/example]

[reference]

[tags], Unix Coding School[/tags]

• Linux Man Pages – gawk command

[/reference]