thread execution order

Hi, I have an app that writes text messages into a pipe and reads it out.
Other programs write into this pipe too. Sometimes the pipe is full and
my app freezes if it wants to write in that moment. It is not an option
for me to open the pipe with O_NONBLOCK, so I thought I could
use threads. Always when something shall be written into the pipe a new
thread is created. These threads may hang on os.write, but they'll write out
the data ASAP.

I wouldn't do this with threads. I'd use select() or similar to see if
the pipe is writable and if it isn't, buffer internally.

"Rembrandt Q Einstein" wrote:

I wouldn't do this with threads. I'd use select() or similar to see if
the pipe is writable and if it isn't, buffer internally. I thought about something like this too, but since I'm not allowed to
use some kinda timer to write out the pending data I can't it that way.
Therefor I wondered to use threads.

Possibly using ONE writing thread, and a Python Queue -- since
you say the message order is significant.

{pseudo-code}

loop
msg = q.get() #block if no message
pipe.write(msg) #can also block if pipe full
Probably need to create the Queue with no limit on messages,
otherwise you're back to blocking in the main routine.

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"Rembrandt Q Einstein" wrote:

I wouldn't do this with threads. I'd use select() or similar to see if
the pipe is writable and if it isn't, buffer internally.

I thought about something like this too, but since I'm not allowed to
use some kinda timer to write out the pending data I can't it that way.
Therefor I wondered to use threads.

You don't need a timer. Just every time your program tries to write, it
first checks the pipe. If it can write, it does. If it can't, it
buffers until the next time it tries.

"Rembrandt Q Einstein" <hercules.rockefeller@springfield.??.us> wrote:

You don't need a timer. Just every time your program tries to write, it
first checks the pipe. If it can write, it does. If it can't, it
buffers until the next time it tries.

What if there is no "next time". The buffered message might be buffered
until
my not yet planned child can program perl (no way, tv is enough)
or Linux is sold in bottles ;-)

THX, Axel

"Rembrandt Q Einstein" wrote:

I wouldn't do this with threads. I'd use select() or similar to see if
the pipe is writable and if it isn't, buffer internally.

I thought about something like this too, but since I'm not allowed to
use some kinda timer to write out the pending data I can't it that way.
Therefor I wondered to use threads.

THX, Axel

"Rembrandt Q Einstein" wrote:

I wouldn't do this with threads. I'd use select() or similar to see if
the pipe is writable and if it isn't, buffer internally.

I thought about something like this too, but since I'm not allowed to
use some kinda timer to write out the pending data I can't it that way.
Therefor I wondered to use threads.