I think I need to give everyone more to go on, so here it is. My matching code looks like the following.

while (content =~ m%One(.*?)three(.?)five\s+six(.*?)this%gs) {
$var1 = $1 ;
$var2 = $2 ;
$var3 = $3 ;
print "$var1\t$var2\t$var3\n" ;
}

[download]

It gives me output that looks like you would expect, say, for example:

two   four   seven

When the code hangs, it prints out the same thing, but then nothing more.

Now, I've made the following change in keeping with your suggestion.

while (content =~ m%One(.*?)three(.?)five\s+six(.*?)this%gs) {
print(STDERR  "[", pos($content), "]") ;
$var1 = $1 ;
$var2 = $2 ;
$var3 = $3 ;
print "$var1\t$var2\t$var3\n" ;
}

[download]

I'm relatively new to PERL and not a professional coder, so I'm not sure what this is supposed to produce, but here's an example of what I am getting.

[
two   four   seven
48430]

[download]

On another match, however, it gives me:

[48226]

three   more   numbers

[download]

When it hangs, it gives me the following.

[50757]

first   three   numbers

second   three   numbers

third   three   numbers
[51826][52896]

[download]

Does this help with understanding the problem?

In reply to Re^2: Regex infinite loop? by Ninth Prince
in thread Regex infinite loop? by Ninth Prince

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