Here is what i'm trying to do :
I want to replace any occurence of the string "abc=123" by "abc=999" except if the pattern is followed by a digit (I want to replace only "abc=123" and not "abc=1234")
One of the most promissing command I tried was :
but the output is :
What I'm trying to get is :
Can anyone help ?
Last edited by nikop51000; 09-05-2012 at 12:23 PM..
Reason: forgot the & after 999 in the "What I'm trying to get" part
I know we can substitute a string using sed but how?
For example: sed 's/(old variable)/(new variable)/ details.dat
Am I suppose to put $old variable or whatever? Because I tried many times, it didnt work by putting $old variable. Am I suppose to enclose it with "" or ''?
Please help (3 Replies)
Hi,
I have a set of files containing strings like I.TEST1_TEST2 or B.ESSA_ESSB for example.
Does somebody know how to substitute these strings whith the same name and an extension "_V1" (ie. I.TEST1_TEST2_V1) using sed command or else ? (3 Replies)
Hi ,
I am stuck up in the below scenario:-
I need to read a file name (eg A.txt) name frm another file (eg B.txt) and then I need to search for a particular expression in A.txt and substitute it with another expression.
How can I use SED inside SHELL Scripting and command prompt as... (2 Replies)
Hi ,
I am stuck up in the below scenario:-
I need to read a file name (eg A.txt) name frm another file (eg B.txt) and then I need to search for a particular expression in A.txt and substitute it with another expression.
How can I use SED inside SHELL Scripting and command prompt as well to... (1 Reply)
Using sed I'm trying to replace 'string' with ']' while retaining case and ignoring words with 'string' in it along with additional characters like 'strings' and those which already contain the ] wrapper. I'm hoping to do it with sed and the right expression, if possible.
Example:
Apple... (2 Replies)
I'm a noob to unix, and I have a line of data like the following:
title=Boston|tcolor=green|desc=Large city in New England|url=www.boston.com
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I have a file with some numbers having single quotes around them which I want to remove.
i.e. '923930' -> 23930
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Hello,
I have two files. File1 is normal txt file and File2 contains list of line numbers.
e.g. File2:
3
6
9
.....
I need to replace a character in File1 in lines (taken from File2). For that I am using a "for" loop:
for i in $(cat File2)
do
sed "$i s/Y/N/" File1
done
but my... (3 Replies)
How can you use sed with a line of code that reads:
67899:Bill:Williams:Maple Dr.:45908600
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I need very simple sed command to change a parameter in a text file.
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set xx 0.5
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Discussion started by: hayreter
7 Replies
LEARN ABOUT OSX
subst
subst(n) Tcl Built-In Commands subst(n)
__________________________________________________________________________________________________________________________________________________NAME
subst - Perform backslash, command, and variable substitutions
SYNOPSIS
subst ?-nobackslashes? ?-nocommands? ?-novariables? string
_________________________________________________________________DESCRIPTION
This command performs variable substitutions, command substitutions, and backslash substitutions on its string argument and returns the
fully-substituted result. The substitutions are performed in exactly the same way as for Tcl commands. As a result, the string argument
is actually substituted twice, once by the Tcl parser in the usual fashion for Tcl commands, and again by the subst command.
If any of the -nobackslashes, -nocommands, or -novariables are specified, then the corresponding substitutions are not performed. For
example, if -nocommands is specified, command substitution is not performed: open and close brackets are treated as ordinary characters
with no special interpretation.
Note that the substitution of one kind can include substitution of other kinds. For example, even when the -novariables option is speci-
fied, command substitution is performed without restriction. This means that any variable substitution necessary to complete the command
substitution will still take place. Likewise, any command substitution necessary to complete a variable substitution will take place, even
when -nocommands is specified. See the EXAMPLES below.
If an error occurs during substitution, then subst will return that error. If a break exception occurs during command or variable substi-
tution, the result of the whole substitution will be the string (as substituted) up to the start of the substitution that raised the excep-
tion. If a continue exception occurs during the evaluation of a command or variable substitution, an empty string will be substituted for
that entire command or variable substitution (as long as it is well-formed Tcl.) If a return exception occurs, or any other return code is
returned during command or variable substitution, then the returned value is substituted for that substitution. See the EXAMPLES below.
In this way, all exceptional return codes are "caught" by subst. The subst command itself will either return an error, or will complete
successfully.
EXAMPLES
When it performs its substitutions, subst does not give any special treatment to double quotes or curly braces (except within command sub-
stitutions) so the script
set a 44
subst {xyz {$a}}
returns "xyz {44}", not "xyz {$a}" and the script
set a "p} q {r"
subst {xyz {$a}}
returns "xyz {p} q {r}", not "xyz {p} q {r}".
When command substitution is performed, it includes any variable substitution necessary to evaluate the script.
set a 44
subst -novariables {$a [format $a]}
returns "$a 44", not "$a $a". Similarly, when variable substitution is performed, it includes any command substitution necessary to
retrieve the value of the variable.
proc b {} {return c}
array set a {c c [b] tricky}
subst -nocommands {[b] $a([b])}
returns "[b] c", not "[b] tricky".
The continue and break exceptions allow command substitutions to prevent substitution of the rest of the command substitution and the rest
of string respectively, giving script authors more options when processing text using subst. For example, the script
subst {abc,[break],def}
returns "abc,", not "abc,,def" and the script
subst {abc,[continue;expr {1+2}],def}
returns "abc,,def", not "abc,3,def".
Other exceptional return codes substitute the returned value
subst {abc,[return foo;expr {1+2}],def}
returns "abc,foo,def", not "abc,3,def" and
subst {abc,[return -code 10 foo;expr {1+2}],def}
also returns "abc,foo,def", not "abc,3,def".
SEE ALSO
Tcl(n), eval(n), break(n), continue(n)
KEYWORDS
backslash substitution, command substitution, variable substitution
Tcl 7.4 subst(n)