SED - Delete - Delete BOTH leading and trailing whitespace from each line

SED - Delete - Delete BOTH leading and trailing whitespace from each line

sed 's/^[ \t]*//;s/[ \t]*$//'

NOTE: Aligns all text flush left.

NOTE: The expression '\t' is used to indicate a tab character (0x09) in the scripts.

Some versions of sed do not recognize the '\t' abbreviation, so when typing these scripts from the command line, you should press the TAB key instead.

'\t' is supported as a regular expression.

Example

Running that command again this file:

testfile

aaa
 bbb
  ccc

returns:

testfile

aaa
bbb
ccc

Example

cat input.txt | sed 's/^[ \t]*//;s/[ \t]*$//' > output.txt

Example - Remove all whitespace (including tabs) from beginning of string

echo "     This is a test" | sed -e 's/^[ \t]*//'

result:

This is a test

Where,

s/ : Substitute command ~ replacement for pattern (^[ \t]*) on each addressed line
^[ \t]* : Search pattern ( ^ – start of the line; [ \t]* match one or more blank spaces including tab)
** : Replace (delete) all matched pattern —-

Table of Contents

SED - Delete - Delete BOTH leading and trailing whitespace from each line

Example

Example

Example - Remove all whitespace (including tabs) from beginning of string