Here is a nice simple example. We read from the DATA file handle but it could just as well be a file handle you open with an open FILE, "<file.txt" or die "Oops $!\n"

while (<DATA>) {
   ($first) = $_ =~ m/^(\S+)/;
    print "$first\n";
}

__DATA__
This is a line.
Another line is here.
  Here's a line.

Line five is this one.
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The while iterates over the filehandle assigning each line to $_. The next line is a standard perl idiom to capture a regex match. We match all non whitespace at the begining of the each line. We specify the beginning with the ^ and the non whitespace with the \S the + after \S specifies 1 or more of (and as much as possible)

You can also do this with split. Split returns an array of values so (split/\s/,$_)[0] is the first value when we split $_ on whitespace. Note that in the example I don't bother to specify $_ as this is the default string that split works on.

while (<DATA>) {
    $first = (split/\s/)[0];
    print "$first\n";
}
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Getting completely carried away you can also do it using substr and index. Index gets you the postion of the first space and substr gets you the string.

while (<DATA>) {
    $first = substr $_, 0, index $_, " ";
    print "$first\n";
}
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Hope this helps.

cheers

tachyon

s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print