Script snippets for piping commands

Script snippets for piping commands

The following scripts do nice things as a part of a pipe.

Table 1.26. List of script snippets for piping commands

script snippet  (type in one line)

effect of command

|find /usr -print	find all files under "/usr"
|seq 1 100	print 1 to 100
| xargs -n 1 <command>	run command repeatedly with each item from pipe as its argument
| xargs -n 1 echo	split white-space-separated items from pipe into lines
| xargs echo	merge all lines from pipe into a line
| grep -e <regex_pattern>	extract lines from pipe containing <regex_pattern>
| grep -v -e <regex_pattern>	extract lines from pipe not containing <regex_pattern>
| cut -d: -f3 -	extract third field from pipe separated by ":" (passwd file etc.)
| awk '{ print $3 }'	extract third field from pipe separated by whitespaces
| awk -F'\t' '{ print $3 }'	extract third field from pipe separated by tab
| col -bx	remove backspace and expand tabs to spaces
| expand -	expand tabs
| sort| uniq	sort and remove duplicates
| tr 'A-Z' 'a-z'	convert uppercase to lowercase
| tr -d '\n'	concatenate lines into one line
| tr -d '\r'	remove CR
| sed 's/^/# /'	add "#" to the start of each line
| sed 's/\.ext//g'	remove ".ext"
| sed -n -e 2p	print the second line
| head -n 2 -	print the first 2 lines
| tail -n 2 -	print the last 2 lines