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Input/Output with multiple coprocesses

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# 1  
Old 09-07-2009
Input/Output with multiple coprocesses
Communication between a parent korn shell script and a coprocess is through read -p and write -p. If there are multiple coprocesses how does the parent script specify which coprocess it wants to read from?

Thanks,
twk
# 2  
Old 09-07-2009
See sec 4.3.6 in this:
Safari Books Online - 0596100299 - Unix in a Nutshell, 4th Edition

What you do is to exec the stdout and stdin for a coprocess to other file descriptors, repeating the process for each alternate coprocess you create.
# 3  
Old 09-07-2009
Gave that a try and it would appear that the largest file descriptor is "9". This means to me that there are 6 descriptors available, 4 - 9. The script I am developing will spawn several hundred processes and 6 are not enough to have 2 descriptors for each coprocess. Am I missing something?
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