Re^3: Set env variables as part of a command

Ok so yeah googled, learned what fork does. Let me ask another probably basic question I could not find in some googling. When I fork the program I execute I need to create an array. I need to return that array to the parent process. How would one do that?

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Re^4: Set env variables as part of a command by afoken (Chancellor) on Feb 18, 2017 at 18:19 UTC
When I fork the program I execute I need to create an array. I need to return that array to the parent process. How would one do that? By serialising and unserialising. Create the array in the child process, write it to a file handle of a pipe, and read that pipe in the parent process. Perl wraps that in `open('-\|')` / `open('\|-')` See perlipc, especially section "Safe Pipe Opens". For simple arrays of simple strings not containing control characters, writing each string on a new line might be sufficient. Otherwise, use Storable, JSON, XML, YAML or something like that. Update: You might need to fork once again from your first child to be able to "return" an array after the external program has finished. Alexander -- Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)	[reply] [d/l] [select]

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Re^4: Set env variables as part of a command
by afoken (Chancellor) on Feb 18, 2017 at 18:19 UTC

When I fork the program I execute I need to create an array. I need to return that array to the parent process. How would one do that?

By serialising and unserialising. Create the array in the child process, write it to a file handle of a pipe, and read that pipe in the parent process. Perl wraps that in open('-|') / open('|-') See perlipc, especially section "Safe Pipe Opens". For simple arrays of simple strings not containing control characters, writing each string on a new line might be sufficient. Otherwise, use Storable, JSON, XML, YAML or something like that.

Update: You might need to fork once again from your first child to be able to "return" an array after the external program has finished.

Alexander

--
Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)

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