Search for a pattern and replace. Help needed

Shell Programming and Scripting
1

I have three variables $a, $b and $c

$a = file_abc_123.txt
$b = 123
$c = 100

I want to search if $b is present in $a. If it is present, then i want to replace that portion by $c.
Here $b = 123 is present in "file_abc_123.txt", so i need the output as "file_abc_100.txt'
How can this be done.

Thanks in advance

2

Which shell or scripting language do you use and what have you tried so far?

3

perl. I tried using pattern matching.

---------- Post updated at 04:44 AM ---------- Previous update was at 04:26 AM ----------

can you give an idea on this plz

---------- Post updated at 04:44 AM ---------- Previous update was at 04:44 AM ----------

can you give an idea on this plz

---------- Post updated at 04:58 AM ---------- Previous update was at 04:44 AM ----------

:confused:

4

Hi irudayaraj,

Try:

$ cat script.pl
use warnings;                                                                                                                                                                                                                                
use strict;                                                                                                                                                                                                                                  
                                                                                                                                                                                                                                             
my $a = "file_abc_123.txt";                                                                                                                                                                                                                  
my $b = 123;                                                                                                                                                                                                                                 
my $c = 100;                                                                                                                                                                                                                                 
                                                                                                                                                                                                                                             
if ( $a =~ m/$b/ ) {                                                                                                                                                                                                                         
        $a =~ s/$b/$c/;                                                                                                                                                                                                                      
}                                                                                                                                                                                                                                            
                                                                                                                                                                                                                                             
printf "%s\n", $a;                                                                                                                                                                                                                           
$ perl script.pl                                                                                                                                                                                                           
file_abc_100.txt

Regards,
Birei