Login or Register to Ask a Question and Join Our Community

Sponsored Content
Full Discussion: sed not taking variable value
Top Forums Shell Programming and Scripting sed not taking variable value Post 303014450 by RudiC on Monday 12th of March 2018 04:49:24 PM
Old 03-12-2018
Quote:
Originally Posted by sdosanjh
Hi All,
Could you please help me, why sed is not able to take variable value when I try to replace using sed.
.
.
.
Wouldn't a better wording be "sed is not taking shell variable value when used in above setup"?
sed by its design / implementation is not meant to take shell variables (there's more suitable tools like awk or perl), and even less so when used like posted in post#1:
- Single quotes prevent shell expansion.
- Single quotes within the parameters might confuse the tool AND users.
- the entire "{script-only-if-no-other-script}" (c.f. man sed on linux Ubuntu 17.10) should be quoted - just to be on the safe side.

Would
Code:
sed "s/\(.*def.monitor.${CODE}.qStart.*\)${cur}\(.*read\)/\1${new}\2/g" file
abcxx.def.monitor.VL.qStart         09:35               read

come close to what you need?
This User Gave Thanks to RudiC For This Post:
sdosanjh
 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

taking every variable and executing the command

Hi, I am trying to export some 50 tables and i want to write a loop and execute the script for every table. I did for one table and its running. Can any one help me for setting a loop and running the script for all the tables thanks (6 Replies)
Discussion started by: srichunduru
6 Replies

2. Shell Programming and Scripting

Sed variable substitution when variable constructed of a directory path

Hello, i have another sed question.. I'm trying to do variable substition with sed and i'm running into a problem. my var1 is a string constructed like this: filename1 filerev1 filepath1 my var2 is another string constructed like this: filename2 filerev2 filepath2 when i do... (2 Replies)
Discussion started by: alrinno
2 Replies

3. Shell Programming and Scripting

using variable in sed

i need to use a value in the Variable to print a particular line from a file using sed command. i tried the below one but its is not working sed -n ' "$var"p ' abc.txt but its is not working please help me to sort out this. (3 Replies)
Discussion started by: Kochu77
3 Replies

4. Shell Programming and Scripting

Insert a line including Variable & Carriage Return / sed command as Variable

I want to instert Category:XXXXX into the 2. line something like this should work, but I have somewhere the wrong sytanx. something with the linebreak goes wrong: sed "2i\\${n}Category:$cat\n" Sample: Titel Blahh Blahh abllk sdhsd sjdhf Blahh Blah Blahh Blahh Should look like... (2 Replies)
Discussion started by: lowmaster
2 Replies

5. Shell Programming and Scripting

Taking sed result in a variable

Hi All, How can i take the following code having three seds into a variable : echo "$DateFileFormat" | sed 's/\./\\\\./g' | sed 's/\$/+/g' | sed 's/\#/'$job_date'/g' I want to get the result stored in a script variable i tried var2=`echo "$DateFileFormat" | sed 's/\./\\\\./g' |... (4 Replies)
Discussion started by: abhinav192
4 Replies

6. Shell Programming and Scripting

Expand an environment variable in sed, when the variable contains a slash

I'm trying to make a sed substitution where the substitution pattern is an environment variable to be expanded, but the variable contains a "slash". sed -e 's/<HOME_DIRECTORY>/'$HOME'/'This gives me the following error: sed: -e expression #1, char 21: unknown option to `s'Obviously this is... (2 Replies)
Discussion started by: Ilja
2 Replies

7. UNIX for Dummies Questions & Answers

SED taking too much time

Hi I am trying to remove some characters from my data file. The data file has huge number of records say 90000 records. I am using sed for this purpose. eg : cat FILENAME|sed 's/;//g' (to remove semi colon ';') However as the data file is too huge , it is taking too much time to give... (3 Replies)
Discussion started by: dashing201
3 Replies

8. Red Hat

How to pass value of pwd as variable in SED to replace variable in a script file

Hi all, Hereby wish to have your advise for below: Main concept is I intend to get current directory of my script file. This script file will be copied to /etc/init.d. A string in this copy will be replaced with current directory value. Below is original script file: ... (6 Replies)
Discussion started by: cielle
6 Replies

9. Shell Programming and Scripting

How to use the variable in sed?

version=git release=r8 echo lp-testsuite-git-r8.x86_64.rpm |sed -e "s/-$version-$release.*//g" I want to get lp-testsuite what's wrong with me ? (1 Reply)
Discussion started by: yanglei_fage
1 Replies

10. Shell Programming and Scripting

Help with taking variable of for loop in textfile

Hi, I am new to unix/linux scripting. I have a text file, listlib.txt where the content: lib1_23 lib34_a ab_li_lab I need to generate a file (.log) of each cell. I am planning to create a (.csh) script that will have for loop with variable taken from listlib.txt. As for now, i have no... (4 Replies)
Discussion started by: mmaz
4 Replies

LEARN ABOUT DEBIAN

shtool-subst

SHTOOL-SUBST.TMP(1)					      GNU Portable Shell Tool					       SHTOOL-SUBST.TMP(1)

NAME

       shtool-subst - GNU shtool sed(1) substitution operations

SYNOPSIS

       shtool subst [-v|--verbose] [-t|--trace] [-n|--nop] [-w|--warning] [-q|--quiet] [-s|--stealth] [-i|--interactive] [-b|--backup ext]
       [-e|--exec cmd] [-f|--file cmd-file] [file] [file ...]

DESCRIPTION

       This command applies one or more sed(1) substitution operations to stdin or any number of files.

OPTIONS

       The following command line options are available.

       -v, --verbose
	   Display some processing information.

       -t, --trace
	   Enable the output of the essential shell commands which are executed.

       -n, --nop
	   No operation mode. Actual execution of the essential shell commands which would be executed is suppressed.

       -w, --warning
	   Show warning on substitution operation resulting in no content change on every file. The default is to show a warning on substitution
	   operations resulted in no content change on all files.

       -q, --quiet
	   Suppress warning on substitution operation resulting in no content change.

       -s, --stealth
	   Stealth operation. Preserve timestamp on file.

       -i, --interactive
	   Enter interactive mode where the user has to approve each operation.

       -b, --backup ext
	   Preserve backup of original file using file name extension ext.  Default is to overwrite the original file.

       -e, --exec cmd
	   Specify sed(1) command directly.

       -f, --file cmd-file
	   Read sed(1) command from file.

EXAMPLE

	#   shell script
	shtool subst -i -e 's;(c) ([0-9]*)-2000;(c) 1-2001;' *.[ch]

	#    RPM spec-file
	%install
	    shtool subst -v -n 
		-e 's;^(prefix=).*;1 $RPM_BUILD_ROOT%{_prefix};g' 
		-e 's;^(sysconfdir=).*;1 $RPM_BUILD_ROOT%{_prefix}/etc;g' 
		`find . -name Makefile -print`
	    make install

HISTORY

       The GNU shtool subst command was originally written by Ralf S.  Engelschall <rse@engelschall.com> in 2001 for GNU shtool.  It was prompted
       by the need to have a uniform and convenient patching frontend to sed(1) operations in the OpenPKG package specifications.

SEE ALSO

       shtool(1), sed(1).

18-Jul-2008							   shtool 2.0.8 					       SHTOOL-SUBST.TMP(1)
All times are GMT -4. The time now is 03:02 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy