What's going on? Do I need to "reset" the search back to the beginning of the $content string?

Yes, you do. The conventional way to use the /g modifier is with a while loop:

while ($text =~ m/.../g) {
  ...
}
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When the while loop terminates the match position associated with $text is at the end, so the next time you match it with a /g modifier the search will begin from the start of the start of the string.

It appears you can reset the last match position by either:

• modifying the variable (even $text .= '' works)
• explicitly setting pos(...), i.e. pos($text) = 0

Here is some test code:

my $text = "aaa";
while ($text =~ m/a/g) { last } # only executes once

pos($text) = 0;
# $text .= '';  # another way to do it

print "matched\n" if ($text =~ m/aaa/g)
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