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
Is there a way to change a field value with sed substitution?
(i.e. change tcolor=green to tcolor=blue)
I figured out: sed... (19 Replies)
I have a file with some numbers having single quotes around them which I want to remove.
i.e. '923930' -> 23930
If it can be done without using sed thats fine. I have tried with sed but can't think how to replace this pattern on only the numbers (13 Replies)
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
Let us say we want to replace Maple Dr. with Oak St. (1 Reply)
Hi everyone,
I need very simple sed command to change a parameter in a text file.
I have a line in this text which is like
set xx 0.5
A program reads this file and does some algebraic calculations. So to make a parameter scan I need to change the value of xx. I thought I can do... (7 Replies)
Discussion started by: hayreter
7 Replies
LEARN ABOUT OPENDARWIN
switch
switch(n) Tcl Built-In Commands switch(n)
__________________________________________________________________________________________________________________________________________________NAME
switch - Evaluate one of several scripts, depending on a given value
SYNOPSIS
switch ?options? string pattern body ?pattern body ...?
switch ?options? string {pattern body ?pattern body ...?}
_________________________________________________________________DESCRIPTION
The switch command matches its string argument against each of the pattern arguments in order. As soon as it finds a pattern that matches
string it evaluates the following body argument by passing it recursively to the Tcl interpreter and returns the result of that evaluation.
If the last pattern argument is default then it matches anything. If no pattern argument matches string and no default is given, then the
switch command returns an empty string.
If the initial arguments to switch start with - then they are treated as options. The following options are currently supported:
-exact Use exact matching when comparing string to a pattern. This is the default.
-glob When matching string to the patterns, use glob-style matching (i.e. the same as implemented by the string match command).
-regexp When matching string to the patterns, use regular expression matching (as described in the re_syntax reference page).
-- Marks the end of options. The argument following this one will be treated as string even if it starts with a -.
Two syntaxes are provided for the pattern and body arguments. The first uses a separate argument for each of the patterns and commands;
this form is convenient if substitutions are desired on some of the patterns or commands. The second form places all of the patterns and
commands together into a single argument; the argument must have proper list structure, with the elements of the list being the patterns
and commands. The second form makes it easy to construct multi-line switch commands, since the braces around the whole list make it unnec-
essary to include a backslash at the end of each line. Since the pattern arguments are in braces in the second form, no command or vari-
able substitutions are performed on them; this makes the behavior of the second form different than the first form in some cases.
If a body is specified as ``-'' it means that the body for the next pattern should also be used as the body for this pattern (if the next
pattern also has a body of ``-'' then the body after that is used, and so on). This feature makes it possible to share a single body among
several patterns.
Beware of how you place comments in switch commands. Comments should only be placed inside the execution body of one of the patterns, and
not intermingled with the patterns.
Below are some examples of switch commands:
switch abc a - b {format 1} abc {format 2} default {format 3}
will return 2,
switch -regexp aaab {
^a.*b$ -
b {format 1}
a* {format 2}
default {format 3}
}
will return 1, and
switch xyz {
a
-
b
{
# Correct Comment Placement
format 1
}
a*
{format 2}
default
{format 3}
}
will return 3.
SEE ALSO
for(n), if(n), regexp(n)
KEYWORDS
switch, match, regular expression
Tcl 7.0 switch(n)