STDIN, STDOUT and pipes

Hi Guys,

OK, I was toying with the idea of using a pipe to pass data from one program to another. The idea was that PGM1 would write to the pipe and PGM2 would read from it - both in the same job. The idea was that in this particular case we could use a pipe in place of a pointer - no need to allocate/reallocate/deallocate or keep track of size. I got an example working nicely, as we already have code using pipes for inter-process communications. However, there would seem to be a 32k limit on the pipe which puts a severe restriction on it.

So I thought - hang on! What about using STDIN and STDOUT. So I knocked up a simple test program to read from a IFS file, write to STDOUT and then read from STDIN and write out to another IFS file. But I am having a problem on the write to STDOUT. I have the file descriptor set to 1 but I'm getting rc2 = -1 and an errno = 3455 (broken pipe).

Any ideas why the write to fd 1 would cause a broken pipe error? My understanding is that fd 0, 1, 2 are reserved for STDIN, STDOUT, & STDERR respectively.

Example snipped for context. The prototypes are from IFSIO_H and data is a 512a field. The read is retrieving 512 bytes and rc1 = 512.

<snip_of_code>
rc1 = read(fd1 :%addr(data) :%size(data));
dow rc1 > 0;
rc2 = write(1 :%addr(data) :rc1);

rc1 = read(fd1 :%addr(data) :%size(data));
enddo;
</snip_of_code>

Of course, if STDIN and STDOUT have a similar size restriction to pipes we may just use a pointer or a temporary stream file.

Your guidance would be most appreciated.

Cheers

Larry Ducie

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