use command_fds::{CommandFdExt, FdMapping}; use std::fs::File; use std::io::stdin; use std::os::fd::AsFd; use std::os::unix::io::AsRawFd; use std::process::Command; // Open a file. let file = File::open("Cargo.toml").unwrap(); // Prepare to run `ls -l /proc/self/fd` with some FDs mapped. let mut command = Command::new("ls"); command.arg("-l").arg("/proc/self/fd"); command .fd_mappings(vec![ // Map `file` as FD 3 in the child process. FdMapping { parent_fd: file.into(), child_fd: 3, }, // Map this process's stdin as FD 5 in the child process. FdMapping { parent_fd: stdin().as_fd().try_clone_to_owned().unwrap(), child_fd: 5, }, ]) .unwrap(); // Spawn the child process. let mut child = command.spawn().unwrap(); child.wait().unwrap();