-/* Liens utiles */ https://www.codequoi.com/pipe-une-methode-de-communication-inter-processus/ https://tldp.org/LDP/lpg/node11.html https://n-pn.fr/t/2318-c--programmation-systeme-execve-fork-et-pipe https://www.youtube.com/watch?v=6xbLgZpOBi8 <-- pipe simulation https://www.youtube.com/watch?v=Mqb2dVRe0uo <-- communication entre processus https://www.youtube.com/watch?v=5fnVr-zH-SE <-- dup() && dup2()
./pipex file1 cmd1 cmd2 file2
$> ./pipex file1 cmd1 cmd2 cmd3 ... cmdn file2
// each cmd needs a stdin (input) and returns an output (to stdout)
infile outfile
as stdin for cmd1 as stdout for cmd2 | PIPE ↑ | |---------------------------| | ↓ | | | cmd1 --> end[1] ↔ end[0] --> cmd2 | | cmd1 |---------------------------| end[0] output reads end[1] is written and sends cmd1 to end[1] output to cmd2 (end[1] becomes (end[0] becomes cmd1 stdout) cmd2 stdin)
External functs. • open, close, read, write, malloc, free, perror, strerror, access, dup, dup2, execve, exit, fork, pipe, unlink, wait, waitpid
https://reactive.so/post/42-a-comprehensive-guide-to-pipex
void child(char **av, int *p_fd, char **env) { int fd;
fd = open_file(av[1], 0);
dup2(fd, 0);
dup2(p_fd[1], 1);
close(p_fd[0]);
exec(av[2], env);
}
void parent(char **av, int *p_fd, char **env) { int fd;
fd = open_file(av[4], 1);
dup2(fd, 1);
dup2(p_fd[0], 0);
close(p_fd[1]);
exec(av[3], env);
}