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perl : Extract filename from full path

To extract the name of the file the quick way is to use substr and rindex commands to strip the path from filename as shown below.

#!/usr/bin/perl

my $path='/path/to/search/filename';
my $fname= substr($path, rindex($path,"/")+1, length($path)-rindex($path,"/")-1);
print "$fnamen";

If you have the luxury of using Perl Packages, then use following solution which is very clean.

#!/usr/bin/perl

use File::Basename;
my $path='/path/to/search/filename';
my $fname = basename($path);
print "$fnamen";
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bash : brace expansion for automatic substitution

Bash expands a list of strings separated by commas with in braces to a list of strings separated by spaces. For example

[unixite@theunixtips:~/> echo 111-{aa,bb,cc}+{xx,yy,zz}-222
111-aa+xx-222 111-aa+yy-222 111-aa+zz-222 111-bb+xx-222 111-bb+yy-222 111-bb+zz-222 111-cc+xx-222 111-cc+yy-222 111-cc+zz-222
unixite@theunixtips:~/>

There should not be any space between suffix/prefix and the start/end bracket. Otherwise it is considered as a separate list. Now coming to a real world example where you can make use of this.

mv process.log{,.old} #This will move process.log to process.log.old
mv process.log.{old,oldest} #This will move process.log.old to process.log.oldest