Re^5: IPC via named pipes, losing some messages

Re: I fixed a bug where a single message could be considered two.

If "C,DIR,1ROSE" is sent over the pipe, the reader might only read "C,DI" which you were treating as an entire message. Then you would proceed to treat "R,1ROSE" as a second message. I fixed this keeping message fragments in the buffer and appending to the unprocessed data in the buffer instead of using a fresh buffer every pass.

The bug in question might not actually exist due to the select, but it's hard to be sure and would be OS-dependent.
Re: I replaced split since you have a record terminator rather than a record separator.

split is useful when your data looks like "ITEM SEP ITEM SEP ITEM". It doesn't make much sense when your data looks like "ITEM TERM ITEM TERM ITEM TERM", as is the case for you.

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Re^6: IPC via named pipes, losing some messages by ftumsh (Scribe) on May 14, 2008 at 11:34 UTC
Ah, I see. Thanks for you time ikegami. The new code works like a charm. Not only does it improve on mine in readability, it appears to be a whole lot more efficient. The load on the machine has gone down! John	[reply]
Re^7: IPC via named pipes, losing some messages by ikegami (Patriarch) on May 14, 2008 at 14:50 UTC
Interesting. Your version only processed data when there's a lull in reading. If the data comes in fast enough, it could be the `select`s become expensive no-ops and `$data .= $buf;` builds up to something huge. In my version, I process data as soon as it comes in.	[reply] [d/l] [select]