Greetings, ye Monks of Perl.

I'm writing something that does a lot of readlink calls, and sometimes it returns some pretty strange stuff. I'm guessing the strangeness is actually coming from my operating system, but I wanted to share and see what you all thought.

Sometimes the returned string contains some non-printing characters followed by a bunch of pretty random looking stuff. Here's an example:

/proc/32433/exe -> /usr/bin/perl.pid]o_ff.jpg (deleted)

[download]

If I pipe that through less, I get to see markers showing me where the non-printing characters are:

/proc/32433/exe -> /usr/bin/perl^@.pid^@]^@^@o_ff.jpg (deleted)

[download]

An ordinary ls -l /proc/32433/exe says /proc/32433/exe -> /usr/bin/perl. I get the same by running the readlink command (/usr/bin/readlink).

So it looks like the correct answer followed by a bunch of other stuff.

If you're on linux, you can try this... 

find /proc -type l -name 'exe' | \
perl -n -e 'chomp($_); print "$_ -> ".readlink($_)."\n";'

[download]
... and you might see what I'm talking about.

Anybody know what's going on here?

I'm on CentOS 5.5 running perl 5.8.8 from the perl-5.8.8-32.el5_5.1 rpm package.

Thanks!

--Pileofrogs

In reply to readlink returning strange stuff by pileofrogs

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