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I'm writing a program using children processes in C. Basically, the children reads distinct files and calculates a summation. Then they need to return it to main process. How can I return from them to main process?

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  • `exit(result)` in child. `waitpid(pid,&status,0) ` trick would work. but only for int value. `status` will hold result – Tauqeer Akhtar Nov 10 '21 at 08:24
  • Note that you can only return values in the range 0..255 via the exit status. That is usually inadequate. – Jonathan Leffler Nov 10 '21 at 08:27
  • You can use shared memory `(shm_open(), shm_unlink(), mmap(), etc.).` . – Tauqeer Akhtar Nov 10 '21 at 08:31

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