{"id":602,"date":"2012-03-25T02:03:30","date_gmt":"2012-03-25T08:03:30","guid":{"rendered":"http:\/\/blog.supportpro.com\/?p=602"},"modified":"2019-10-30T05:50:08","modified_gmt":"2019-10-30T11:50:08","slug":"commenting-multiple-lines-in-a-shell-script-using-vivim-in-a-single-step","status":"publish","type":"post","link":"https:\/\/www.supportpro.com\/blog\/commenting-multiple-lines-in-a-shell-script-using-vivim-in-a-single-step\/","title":{"rendered":"Commenting Multiple Lines in a Shell Script Using VI\/Vim in a Single Step"},"content":{"rendered":"

A text editor like vi or vim can be used to comment multiple lines in a shell script (or any other script or configuration file) in a single go rather than adding # or whatever that goes for a comment for the script in question.<\/p>\n

Open the file to be edited using vi\/vim using the command vi filename (where filename can be replaced by the name of the file), now enter the command mode by pressing: .In order to comment multiple lines ( i.e. to add a # to the beginning of the line), say lines from 5 to 10 in the script, type the command
\n:5,10s\/^\/#\/ # : in the command is part of entering the editing\/ex mode in vi.<\/p>\n

Note# The command : set nu can be used to view line numbers in vi\/vim
\nClarification
\nGeneral Syntax
\n==============================================
\n:%s\/r1\/r2\/ is the syntax used for string substitution in vi\/vim
\nSyntax split
\n: Enter command mode
\n% Perform the command on all lines
\ns Short form for :substitute command
\nr1 Can be replaced with any string in the script\/file that is to be replaced
\nr2 Can be replaced with any string which should replace the string r1 in the script\/file
\n\/ Used a separator
\nChanges from syntax in executed command
\n============================================<\/p>\n

In the command that we used for substitution\/adding comments to lines starting from 5 to 10
\n% has been replaced with 5,10 so that the command will be executed only for lines starting from 5 to 10
\n^ caret [^ ] matches the position before the first character in the string (hence in the command that we executed the substitution takes place for the position before the first character[=r1])
\n# Replacement for r2 in syntax (i.e. # is used as the character\/string which substitutes r1[position before the first character])<\/p>\n

Comment removal<\/h4>\n

In order to uncomment multiple lines (we will remove # from the lines that we have commented, i.e. from 5 to 10) we can use the command
\n:5,10s\/^#\/\/
\nClarification
\n^# Matches all characters starting with # (since ^ means position before the first character, ^x [x can be replaced with any character which does not hold a special meaning in bash, or \\x if x has got a special meaning] will match any line which has got x as the character at the first character)
\n\/\/ Two \/s without any in between space :: hence substitution will completely remove # from the beginning without adding anything
\nCommenting all lines in a script\/file
\nOpen the file in vi\/vim and use the command
\n:%s\/^\/#\/g<\/p>\n

g stands for global (so that the substitution will occur globally, i.e. for all lines in the script)
\nAll the rest have already been explained in General Syntax
\nNote: For php files which treat ; as the commenting character instead of # , # can be replaced with ; i.e. for commenting all lines in a php file we can use the command %s\/^\/;\/g<\/p>\n

If you require help, contact SupportPRO Server Admin<\/a><\/p>\n

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