Chris: On Tue, Aug 11, 2015 at 02:24:13PM +0200, Chris Knipe wrote: > Hi All,
Hello,
> I'm reading "binary" from a socket, and just like a normal email message on
> the SMTP protocol (for example), the data is terminated by \r\n.\r\n
>
>
>
> I'm saying "binary" because the data stream does include yEnc data (or
> character codes > 127)
>
>
>
> I'm having issues to exit my read loop when I receive the termination
> characters...
>
>
>
> my $numBytesToRead = 512;
>
> my $buffer;
>
> while ($bytesRead = read($TCPSocket, $buffer, $numBytesToRead)) {
>
> if ($buffer =~ m/\r\n\.\r\n$/) {
>
> print $buffer;
>
> last;
>
> }
>
> }
>
>
>
> I'm obviously doing this wrong :( Can anyone perhaps show me the light?
I can think of a couple of problems.
Firstly, if the handle isn't being read with binmode set then
perhaps the \r\n are being converted to \n (if this is Windows)?
How are you creating/initializing the socket?
You used to be able to set binary mode on a file handle using
binmode() like this:
binmode $fh;
Similarly, the character encoding of the data on the socket could
matter. You said there are character codes above 127. Does that
mean the encoding is 8-bit such as [extended] ASCII or latin1, or
do you mean the character codes are WAY above 127? Character
encoding could be another culprit if the \r and \n characters are
encoded differently in the stream than you (and Perl) expects.
Using the IO layers or the explicit Encode module you should be
able to decode the stream into a Perl string that Perl
understands properly.
You can attach an IO layer to the file handle by passing an
additional argument to binmode:
binmode $fh, ':encoding(UTF-8)';
Lastly, you're reading from a socket so there's no guarantee that
the buffer string is going to necessarily end at the termination
boundary. Perhaps the protocol guarantees that, but the socket
surely doesn't. You may need to look for that terminating
sequence in the middle of the buffer.
You could use Data::Dumper and/or various poor-man's debugging
techniques to try to identify the problem here. You could write
what you read to a file and inspect that file with a hex editor
afterward. Alternatively, you could invoke perl's debugger with
the -d flag and inspect the program state in real-time.
Does any of that help?
Regards,
--
Brandon McCaig <bamcc...@gmail.com> <bamcc...@castopulence.org>
Castopulence Software <https://www.castopulence.org/>
Blog <http://www.bambams.ca/>
perl -E '$_=q{V zrna gur orfg jvgu jung V fnl. }.
q{Vg qbrfa'\''g nyjnlf fbhaq gung jnl.};
tr/A-Ma-mN-Zn-z/N-Zn-zA-Ma-m/;say'
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