Comment lines in FSTAB using perl Post: 302671875

Sponsored Content

Top Forums Shell Programming and Scripting Comment lines in FSTAB using perl Post 302671875 by bakunin on Saturday 14th of July 2012 10:53:17 PM

07-14-2012

Registered User

Are you insisting in PERL? Because in fact this is a simple operation and to use PERL for this is probably overkill of the extreme sort. The following solution is sed and will do the job:

Code:

sed 's/^[<spc><tab>]*zin46fil01:\/vol\/fil01vol09\/soft1\/\_TOOLS_\/dist \/_TOOLS_\/.dist15/# &/' /etc/fstab > /tmp/sed.$$
mv /etc/fstab /etc/fstab.${DATE}
mv /tmp/sed.$$ /etc/fstab

I assumed the variable "$DATE" here, which is part of my environment, because i like to have date-coded backup files if i let something change via a script. If you don't have such a variable either create one before or even dump the command altogether if you don't need a backup copy.

Replace "<spc>" and "<tab>" with literal spaces/tabs. If you have more than one line to comment out just duplicate the line and change the path accordingly. The "&" in the replacement part means "everything matched by the regexp before":

Code:

sed 's/^[<spc><tab>]*\/path\/to\/mount1/# &/
     s/^[<spc><tab>]*\/path\/to\/mount2/# &/' /etc/fstab > /tmp/sed.$$
mv /etc/fstab /etc/fstab.${DATE}
mv /tmp/sed.$$ /etc/fstab

I hope this helps.

bakunin

bakunin

View Public Profile for bakunin

Find all posts by bakunin

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

how to comment multiple lines in unix

hi all, please help me how to comment multiple lines in unix script. thanks in advance --bali

2. UNIX for Dummies Questions & Answers

comment lines

Is there a command to put a comment (#) in a whole part of a shell script?

3. Shell Programming and Scripting

using awk to comment out lines to the end of file

Hello, I have a file as follow a b c c d d e I would like to write a awk command to insert # from the first occurence of "c" to the end of the files. OUTPUT should be like this a b #c

4. Shell Programming and Scripting

Need perl regular expression to remove the comment

I need a perl substitution to remove only the comment in the line . That line may have '#' with in double quotes .I used the following , s/(^.*\".+?#.+?\".+?)(#.*)/$1/g It works for , print " not a comment # not a comment " . "not a comment # not a comment" ; # It is a comment ...

5. UNIX for Dummies Questions & Answers

Trying to show lines in INI files until the comment character (#)

I have a working directory on a server with over 100 INI files. For the most part, they are configured the same way. Each line will contain 1 or none variables listed from the first character in the line such as VariableName=0. Unfortunately there are comments everywhere using the...

6. Shell Programming and Scripting

How can i comment out a section between two particular lines

I want to find out which files under /etc have the the following section: and then i would like to comment out the above section in all the files. Please help.

7. UNIX for Dummies Questions & Answers

Comment lines in file without vi editor

Legends, Can you please help me in following. I need to comment lines from �/tmp/a.txt� from the line A to line B through the command prompt only. Please use variables not direct values like 2 or 5 It can be done with VI editor but it's not matches with my requirement (: 2,5 s/^/#/g). ...

8. Shell Programming and Scripting

Comment ( -- ) lines from 10 to 25 for every .sql file

Platform : RHEL 5.4 I have several .sql files in a directory. I want to comment lines 10 to 25 for all .sql files. How can I do this ? The symbol for comment in SQL is -- eg: -- select salary from emp where empname = 'URS' ;

9. Shell Programming and Scripting

Perl one liner to wrap comment lines

Greetings fellow scripters. I find myself editing multiple files, sometimes with the same bits of information. My bash script, a changelog, and a plist file (OS X). Once I realized this, I thought why not script part of this process (and so it begins). In any case, I've solved several of the...

10. UNIX for Beginners Questions & Answers

Remove Comment Lines From Script/Input File

Hello, I have a SAS code that predominantly has comments line and the real code like below and i want to remove ONLY THE COMMENTS from the code in the single line or spanned across multiple lines. /******************************************************************** *** This Is a Comment...

LEARN ABOUT BSD

setfsent

GETFSENT(3)						     Library Functions Manual						       GETFSENT(3)

NAME

       getfsent, getfsspec, getfsfile, getfstype, setfsent, endfsent - get file system descriptor file entry

SYNOPSIS

       #include <fstab.h>

       struct fstab *getfsent()

       struct fstab *getfsspec(spec)
       char *spec;

       struct fstab *getfsfile(file)
       char *file;

       struct fstab *getfstype(type)
       char *type;

       int setfsent()

       int endfsent()

DESCRIPTION

       Getfsent,  getfsspec,  getfstype,  and  getfsfile each return a pointer to an object with the following structure containing the broken-out
       fields of a line in the file system description file, <fstab.h>.

	      struct fstab {
		   char *fs_spec;
		   char *fs_file;
		   char *fs_type;
		   int	fs_freq;
		   int	fs_passno;
	      };

       The fields have meanings described in fstab(5).

       Getfsent reads the next line of the file, opening the file if necessary.

       Setfsent opens and rewinds the file.

       Endfsent closes the file.

       Getfsspec and getfsfile sequentially search from the beginning of the file until a matching special file name or file system file  name	is
       found, or until EOF is encountered.  Getfstype does likewise, matching on the file system type field.

FILES

       /etc/fstab

SEE ALSO

       fstab(5)

DIAGNOSTICS

       Null pointer (0) returned on EOF or error.

BUGS

       All information is contained in a static area so it must be copied if it is to be saved.

4th Berkeley Distribution					   May 12, 1986 						       GETFSENT(3)

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

how to comment multiple lines in unix

Discussion started by: balireddy_77

2. UNIX for Dummies Questions & Answers

comment lines

Discussion started by: vero_81

3. Shell Programming and Scripting

using awk to comment out lines to the end of file

Discussion started by: phamp008

4. Shell Programming and Scripting

Need perl regular expression to remove the comment

Discussion started by: karthigayan