UNIX for Dummies Questions & Answers

sed 's/.*\[\(.*\)\].*/\1/g' sent.txt
sed 's/\(.*\[\).*\(\].*\)/\1\2/g' sent.txt

sed 's/.*\[\(.*\)\].*/\1/g' inputfile > outputfile

sed 's/\(.*\[\).*\(\].*\)/\1\2/g' inputfile > outputfile

grep -o "\[.*\]" infile
[kidnapped]
[committed]

sed 's/\[.*\]/\[ \]/' infile

1. If the boss's son had been [ ], someone would have asked for money by now.
2. Look, I haven't [ ] a crime, so why can't you let me go?

 $ cat file
1. If the boss's son had been [kidnapped], someone would have asked for [ money  ]by now.
2. Look, I haven't [committed] a crime, so why can't [   you            ] let me go?

$ ruby -ne 'puts $_.scan(/\[.*?\]/)' file 
[kidnapped]
[ money  ]
[committed]
[   you         ]

$ ruby -ne 'puts $_.gsub(/\[.*?\]/,"[]")' file
1. If the boss's son had been [], someone would have asked for []by now.
2. Look, I haven't [] a crime, so why can't [] let me go?

 
$ sed 's/\[.*\]/\[ \]/' file 
1. If the boss's son had been [ ]by now. 
2. Look, I haven't [ ] let me go?

awk -F"[][]" '{print $2 > "words"}{$2="[ ]"}1' file > newfile