Redirection inside call to execvp() not working

Question

I\'ve been implementing a small program that executes a given command using execvp(). It works fine when not using redirection, but when I run a command such as:

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Answer 1

Your "small program that executes a given command" is essentially a shell. Since you are writing a shell, it is your job to implement redirections with whatever syntax you desire. The > redirection operator is not a feature of the kernel, it is a shell feature.

To implement sh-style redirection, you must parse the command, locate the redirection operators, open the files and assign them to input/output descriptors. This must be done before calling execvp. Look up the dup2 system call.