Issue
Im trying to comment out lines within a file by a specific word. However there are multiple lines with a similar word.
BBB-m more info
BBB more info
BBB-a more info
BBB-w more info
Im looking to comment out the line with just 'BBB' Is this possible? Thank you!
sed -i -- 's/BBB/; BBB/g' $file
Solution
You can use
awk '$1 == "BBB"{$0="; "$0}1' file > tmp && mv tmp file
sed 's/^BBB[[:space:]]/; &/' file > tmp && mv tmp file
sed -E 's/^BBB([[:space:]]|$)/; &/' file > tmp && mv tmp file
The '$1 == "BBB"{$0="; "$0}1' awk command means that if the first field value is equal to BBB, a ; is appended at the line start. Else, the line is output as is.
The 's/^BBB[[:space:]]/; &/' sed command matches a line that starts with BBB and any one whitespace and then is replaced with ;, space and the matched text. The -E POSIX ERE variation with ^BBB([[:space:]]|$) allows matching BBB as a standalone line.
See the online demo:
#!/bin/bash
s='BBB-m more info
BBB more info
BBB-a more info
BBB-w more info'
awk '$1 == "BBB"{$0="; "$0}1' <<< "$s"
echo "---"
sed 's/^BBB[[:space:]]/; &/' <<< "$s"
Both return
BBB-m more info
; BBB more info
BBB-a more info
BBB-w more info
Answered By - Wiktor Stribiżew Answer Checked By - Willingham (WPSolving Volunteer)