Feel free with Open Source Software

sed

Managing spaces, tabs and new lines

 sed 's/^[ ^t]*//' file

Delete trailing whitespace (spaces/tabs) from end of each line

 sed 's/[ ^t]*$//' file               # see note on '^t', above

Delete BOTH leading and trailing whitespace from each line

 sed 's/^[ ^t]*//;s/[ ^]*$//' file    # see note on '^t', above

Removing the last three characters from every filename

 cat files | sed 's/\(.*\).../\1/'

Removing first character from each filename/string

 cat files |sed 's/.\(.*\)/\1/'

Under UNIX: convert DOS newlines (CR/LF) to Unix format

 sed 's/.$//' file    # assumes that all lines end with CR/LF
 sed 's/^M$// file    # in bash/tcsh, press Ctrl-V then Ctrl-M

Under DOS: convert Unix newlines (LF) to DOS format

 sed 's/$//' file                     # method 1
 sed -n p file                        # method 2

Delete all CONSECUTIVE blank lines from file except the first. This method also deletes all blank lines from top and end of file. (emulates "cat -s")

 sed '/./,/^$/!d' file       # this allows 0 blanks at top, 1 at EOF
 sed '/^$/N;/\n$/D' file     # this allows 1 blank at top, 0 at EOF

Delete all leading blank lines at top of file (only).

 sed '/./,$!d' file

Delete all trailing blank lines at end of file (only).

 sed -e :a -e '/^\n*$/{$d;N;};/\n$/ba' file

Delete leading whitespace (spaces, tabs) from front of each line aligns all text flush left

 sed 's/^[ \t]*//' # see note on '\t' at end of file

Delete trailing whitespace (spaces, tabs) from end of each line

 sed 's/[ \t]*$//' # see note on '\t' at end of file

Delete BOTH leading and trailing whitespace from each line

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

If a line ends with a backslash, join the next line to it.

 sed -e :a -e '/\\$/N; s/\\\n//; ta' file

If a line begins with an equal sign, append it to the previous line (and replace the "=" with a single space).

 sed -e :a -e '$!N;s/\n=/ /;ta' -e 'P;D' file

Center all text in the middle

In method 1, spaces at the beginning of the line are significant, and trailing spaces are appended at the end of the line.

 sed -e :a -e 's/^.\{1,77\}$/ & /;ta'

In method 2, spaces at the beginning of the line are discarded in centering the line, and no trailing spaces appear at the end of lines.

 sed -e :a -e 's/^.\{1,77\}$/ &/;ta' -e 's/\( *\)\1/\1/'

Print only lines of less than 65 characters

 sed -n '/^.\{65\}/!p' # method 1, corresponds to above
 sed '/^.\{65\}/d' # method 2, simpler syntax

Search and replace

Substitute "foo" with "bar" on each line

 sed 's/foo/bar/' file        # replaces only 1st instance in a line
 sed 's/foo/bar/4' file       # replaces only 4th instance in a line
 sed 's/foo/bar/g' file       # replaces ALL instances within a line

Substitute "foo" with "bar" ONLY for lines which contain "baz"

 sed '/baz/s/foo/bar/g' file

EMAIL

Get Usenet/e-mail message header. Deletes everything after first blank line

 sed '/^$/q' 

Get Usenet/e-mail message body. Deletes everything up to first blank line

 sed '1,/^$/d' 

Get Subject header, but remove initial "Subject: " portion

 sed '/^Subject: */!d; s///;q'

Get return address header

 sed '/^Reply-To:/q; /^From:/h; /./d;g;q'

Parse out the address proper. Pulls out the e-mail address by itself from the 1-line return address header (see preceding script)

 sed 's/ *(.*)//; s/>.*//; s/.*[:<] *//'

Add a leading angle bracket and space to each line (quote a message)

 sed 's/^/> /

Delete leading angle bracket & space from each line (unquote a message)

 sed 's/^> //'

Remove most HTML tags (accommodates multiple-line tags)

 sed -e :a -e 's/<[^<]*>/ /g;/</{N;s/\n/ /;ba;}' 

Extract multi-part uuencoded binaries, removing extraneous header info, so that only the uuencoded portion remains. Files passed to sed must be passed in the proper order. Version 1 can be entered from the command line; version 2 can be made into an executable Unix shell script. (Modified from a script by Rahul Dhesi.)

 sed '/^end/,/^begin/d' file1 file2 ... fileX | uudecode # vers. 1
 sed '/^end/,/^begin/d' $* | uudecode # vers. 2

Mix

 sed G file

Sources

• http://www.student.northpark.edu/pemente/sed/sedfaq3.html
• http://www.unixguide.net/unix/sedoneliner.shtml

I appreciate if you give some comment about this page. Please go ahead.
Your e-mailaddress will not be published it is only to contact you (if needed).

 

Your name
Your e-mailaddress
Your comment here...
To prefent robots to use this form I ask you kindly to type the next characters in the input field.