Hi,

I have a parent process that forks 10 children. I would like each child to get a copy of a 'master' socket, do some work, and then write to master socket - atomically.

Unfortunately, 1 out 10 times I run the script, the results are garbled - my current theory is the children are not doing atomic writes to the socket.

I've tried: 

* set autoflush to on ($| = 1)
* using print and syswrite (both are garbled)
* flocking the socket filehandle in the child processes

[download]
Flocking the socket filehandle does not grant an exclusive lock.

The situation it similar to multiple web servers appending to a log file. I've read that one solution is to set the filehandle to '>> append' mode and use syswrite - but I'm not sure if this is going to work with sockets.

I'm also thinking about trying to 'lock' the socket by using a filesystem lock on a PID file - but this seems a bit kludgy.

And ideas?

Regards,

Nige

p.s. prior to forking the children I copy the socket to STDOUT with: *STDOUT = *{$c}; # $c = socket

Edit by tye

In reply to forking() flocking() on sockets by Anonymous Monk

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