Linux Programming Lecture Notes

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Linux Programming

If we want to have a parent process regularly check whether a specific child process had terminated, we could use the call,

which will return zero if the child has not terminated or stopped or child_pid if it has. Input and Output Redirection

We can use our knowledge of processes to alter the behavior of programs by exploiting the fact that open file descriptors are preserved across calls to fork and exec. Try It Out - Redirection

1. Here's a very simple filter program, upper.c , to convert all characters to uppercase:

When we run this program, it reads our input and converts it:

D.Koteswararao

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