named pipe problem

Root Boy Jim rbj at dsys.ncsl.nist.gov
Sat Sep 2 02:32:48 AEST 1989


? From: coolbean <nieters at copernicus.crd.ge.com>

[program deleted]

? If the program runs correctly, you will see the printf message of
?     printf("%s: writing %s\n", argv[0], packet);
? followed by the printf message of 
?     printf("%s: preparing to read packet\n", argv[0]);
? after which the program will block indefinately on the read().

I think your problem is opening the pipe O_RDWR both times.
Try opening it O_RDONLY *first* and then O_WRONLY, or just
use the first file descriptor if you use O_RDWR.

I think that opening a FIFO for write access with no one to read it
blocks, but I can't find the reference in the SunOS 3.5 manuals.
That's why you have to open it for read access first.

? --ed

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