Is there any differences between ' single quote and " double quotes....can u explain it in detail........
See man bash under the section Quoting
Code:
Enclosing characters in single quotes preserves the literal value of each character within
the quotes. A single quote may not occur between single quotes, even when preceded by a
backslash.
Enclosing characters in double quotes preserves the literal value of all characters within
the quotes, with the exception of $, ?, and \. The characters $ and ? retain their spe-
cial meaning within double quotes. The backslash retains its special meaning only when
followed by one of the following characters: $, ?, ", \, or <newline>. A double quote may
be quoted within double quotes by preceding it with a backslash. When command history is
being used, the double quote may not be used to quote the history expansion character.
Hi,
I'm trying to do the following , I have certain variables in a file and then I want to check for these variables in a certain cobol file to see if they contain a certain package if so replace them with value 1 but but that last line is giving problems:
# for each variable in SQL file
... (1 Reply)
Hi,
I'm trying to do the following , I have certain variables in a file and then I want to check for these variables in a certain cobol file to see if they contain a certain package if so replace them with value 1 but but that last line is giving problems:
# for each variable in SQL file
... (1 Reply)
Hi guys,
I want to replace certain values with the number 1.
But it is also replacing other values which contain the value I want to replace. e.g.:
I want to replace ID-INTERNAL with 1, that's no problem but it will also replace ID-INTERNAL-NON-REM with 1-NON-REM
I don't want to... (10 Replies)
when i do something like substituting a particular thing with a system variable, i am unable to do that expect the varible name getting into that.
for ex.. i tried,
sed -e 's/date/`date`/g' <if >of
but i got date replaced with "`date`" and not with the actual date ..
same case happened... (5 Replies)
Hi,
I'm trying to use sed to delete the last three lines of a file. I currently have:
# get the amount of lines in the file
foldernum=`wc -l File_In.txt | cut -c1-8`
# remove the lines in the file
sed "${foldernum}-3,${foldernum}d" File_In.txt > File_Out.txt
I get the error - sed:... (5 Replies)
HELP!!!
I'm keep getting "sed: Function s/PETS/dog cannot be parsed."
I have 2 files that list...
# cat FILE1.txt
dog
cat
mouse
# cat FILE2.txt
my pets are
PETS
I put this into a variable...
# A=`cat FILE1.txt`
# sed "s/PETS/$A" FILE2.txt > FILE3.txt (5 Replies)
I'm trying to get sed to cut and replace using variables, but it doesnt seem to work, when I run this the mod time of the file does get updated. Is my syntax incorrect in the sed command?
Thanks
#!/usr/bin/ksh
#Modify header
set -x
HEAD=$(cat PBN2CPR1.TXT | awk 'BEGIN { FS = ","... (1 Reply)
All
I am trying to produce the following in /etc/ssh/sshd_config,
# IPv4 only
#ListenAddress 0.0.0.0
# IPv4 & IPv6
ListenAddress ::
to
# IPv4 only
ListenAddress <user-entry>
ListenAddress <user-entry>
# IPv4 & IPv6
#ListenAddress ::
The number of user entries can vary.
... (1 Reply)
Im trying to use sed to print value that matches the value in variable and all lines after that.
grep "Something" test.txt | sed -e '/{$variable}/,$b' -e 'd'
I cant get it work, if I replace the $variable with the value it contains, it works fine... (10 Replies)
Discussion started by: olkkis
10 Replies
LEARN ABOUT LINUX
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)