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(Created page with "=awk= pattern {action} pattern {action} $ awk '{print $2}' /etc/fstab $ awk '/^[^#]/ {print $2}' /etc/fstab to filter out comment lines - starting with # print first f...") |
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$ awk '{print $2}' /etc/fstab | $ awk '{print $2}' /etc/fstab | ||
to filter out comment lines - starting with # | |||
$ awk '/^[^#]/ {print $2}' /etc/fstab | $ awk '/^[^#]/ {print $2}' /etc/fstab | ||
print first field from password file using field seperator ':' | print first field from password file using field seperator ':' | ||
| Line 18: | Line 18: | ||
$ awk '{ sum=0; for (i=1; i<=NF; i++) sum +=$i; print sum/NF; }' | $ awk '{ sum=0; for (i=1; i<=NF; i++) sum +=$i; print sum/NF; }' | ||
{| | |||
NF | |- | ||
| NF || number of fields in the current line | |||
|- | |||
| NR || the current record number (line number) | |||
|- | |||
| FS || input field seperator (space by default) | |||
|- | |||
| RS || record seperator (newline by default) | |||
|- | |||
| Example || Example | |||
|- | |||
| Example || Example | |||
|- | |||
| Example || Example | |||
|- | |||
| Example || Example | |||
|- | |||
| Example || Example | |||
|} | |||
Revision as of 16:05, 9 October 2014
awk
pattern {action}
pattern {action}
$ awk '{print $2}' /etc/fstab
to filter out comment lines - starting with #
$ awk '/^[^#]/ {print $2}' /etc/fstab
print first field from password file using field seperator ':'
$ awk -F: '{print$1}' /etc/passwd
print only user ID > 500
$ awk -F: '$3>=500 {print$1}' /etc/passwd
display average of numbers entereed on a line:
$ awk '{ sum=0; for (i=1; i<=NF; i++) sum +=$i; print sum/NF; }'
| NF | number of fields in the current line |
| NR | the current record number (line number) |
| FS | input field seperator (space by default) |
| RS | record seperator (newline by default) |
| Example | Example |
| Example | Example |
| Example | Example |
| Example | Example |
| Example | Example |