#!/usr/local/bin/perl -w
use strict;

my $string = 'begin$end';
$string =~ s/\$/tmp/g;
print "$string\n";
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begintmpend
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Your error must lie elsewhere, as the following code works for me:

#!/usr/bin/perl
use strict;

my $string = 'The price for one night is 10$, the price for two nights
+ is 100$, cash!';
print "String before:\n";
print "$string\n";

$string =~ s!\$! dollar!g;

print "String after:\n";
print "$string\n";
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That works for me, I think you'll have to search for the problem elsewhere. Make sure the dollar signs are in the sting at first place, you have to escape them in a double-quoted string, like:

$x = "The large one costs \$3.50, the small one \$2.50.\n"; 
$x=~s/\$/tmp/g; 
print $x;
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my $string = 'aa$aa';
$string =~ s/\$/tmp/g;
print "$string\n";
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aatmpaa
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$a = '$priyal';
$a =~ s/\Q$\E/tmp/g;
print $a;

o/p:tmppriyal
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This is plain wrong. It just can't work. Did you try it before posting? Do you know what \Q is for? (It's for escaping regexp metacharacters from strings interpolated in regexen.)

From perlop, section Quote and Quote-like Operators:

You cannot include a literal "$" or "@" within a "\Q" sequence. An unescaped "$" or "@" interpolates the corresponding variable, while escaping will cause the lit- eral string "\$" to be inserted. You'll need to write something like "m/\Quser\E\@\Qhost/".

It doesn't produce that output when I run it. In fact it doesn't change the string at all. Did you actually test it?

Makeshifts last the longest.