my $s="TARGET=toto"; 
my ($word)= ($s=~/TARGET\s*=\s*(\w+)/);
print "word: $word\n";'
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But you should really read the doc (perldoc perlre) or books like the Camel if you know that little and want to use Perl.

What do you mean by string? Do you mean everything that follows "TARGET=" and isn't a space? The general regex looks like this:

my ( $target ) = ( $string =~ /TARGET=\s*(\S+)/ );
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Cheers,
Ovid

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while (<FILE>) {
    last if /TARGET\s?=\s?(\S*)\s/;
}
my $value = $1 || "not found";
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If $1 was set before the while loop and the while loop fails, $value will have garbage in it.

Cheers,
Ovid

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And the ever-popular:

my $word;
{
  # Memory is cheap...for some applications
  local $/ = undef;
  open( FILE, "< $file" ) or die( "Ack: $!" );
  my $whole_file = <FILE>;
  close FILE;
  # Assume whitespace delimiting 
  ( $word ) = $whole_file =~ /TARGET\s*=\s*(\S+)/;
}
# $word is now set to our value or undefined
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This slurps the entire file into memory and so isn't generally a good idea, but a variant of this approach *is* useful for more complex multi-line patterns. Particularly when you can use $/ = '\n\n'; or similar instead of $/ = undef; This can make many parsing jobs easier.

Basically, if you find yourself trying to keep state when parsing a multi-line expression, always consider changing the definition of '$/', it is a very powerful tool.

For those unfamiliar with this, evaluating <FOO> in a scalar context reads one 'line' from the filehandle FOO.

The definition of the end of a line is defined by the pattern held in the '$/' variable. You can set this to whatever you want to define your own line-endings.

Note bene: Don't use this to hack around DOS/Unix line ending conventions (CRLF versus LF). If you have problems with this look at the 'binmode' function call.

Hmm....am I far enough off-topic yet? Time to stop this...

$1 will not contain the word from the regex, because the special regex variables are automatically localized to the enclosing blocks. As perlre explains it:

       $<digits>
               Contains the subpattern from the corresponding set
               of parentheses in the last pattern matched, not
               counting patterns matched in nested blocks that
               have been exited already.  (Mnemonic: like
               \digits.)  These variables are all read-only.
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Since the while block has been exited, by the time you check $1 it contains the value it held before the while block was executed.

Try this instead:

my $value = 'not found';
while (<FILE>) {
    $value = $1, last if /TARGET\s?=\s?(\S*)\s/;
}
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