pipex

Pipex

This project will let you discover in detail a UNIX mechanism that you already know by using it in your program.

Mandatory part

Key	Value
Program name	pipex
Turn in files	Makefile, *.h, *.c
Makefile	NAME, all, clean, fclean, re
Arguments	file1 cmd1 cmd2 file2
External functions	- open, close, read, write, malloc, free, perror, strerror, access, dup, dup2, execve, exit, fork, pipe, unlink, wait, waitpid - ft_printf and any equivalent YOU coded
Libft authorized	Yes
Description	This project is about handling pipes.

Your program will be executed as follows:

./pipex file1 cmd1 cmd2 file2

It must take 4 arguments:

• file1 and file2 are file names.
• cmd1 and cmd2 are shell commands with their parameters.

It must behave exactly the same as the shell command below:

$> < file1 cmd1 | cmd2 > file2

Examples

$> ./pipex infile "ls -l" "wc -l" outfile

Should behave like: < infile ls -l | wc -l > outfile

$> ./pipex infile "grep a1" "wc -w" outfile

Should behave like: < infile grep a1 | wc -w > outfile

Requirements

Your project must comply with the following rules:

• You have to turn in a Makefile which will compile your source files. It must not relink.
• You have to handle errors thoroughly. In no way your program should quit unexpectedly (segmentation fault, bus error, double free, and so forth).
• Your program mustn't have memory leaks.
• If you have any doubt, handle the errors like the shell command:
  < file1 cmd1 | cmd2 > file2

Bonus part

You will get extra points if you:

• Handle multiple pipes.

  This:

   $> ./pipex file1 cmd1 cmd2 cmd3 ... cmdn file2

  Should behave like:

   < file1 cmd1 | cmd2 | cmd3 ... | cmdn > file2

• Support << and >> when the first parameter is here_doc.

  This:

   $> ./pipex here_doc LIMITER cmd cmd1 file

  Should behave like:

   cmd << LIMITER | cmd1 >> file