Crate rust_shell
source ·Expand description
Rust shell - shell script written in rust.
This is not an officially supported Google product
Rust shell is a helper library for std::process::Command to write shell script like tasks in rust. The library only works with unix-like operation systems.
Run command
run!
macro creates a ShellCommand instance which you can run by run()
method.
#[macro_use] extern crate shell;
// Run command by cmd! macro
cmd!("echo Hello rust shell!").run().unwrap();
// Contain white space or non-alphabetical characters
cmd!("echo \"%$#\"").run().unwrap();
// Pass an argument
let name = "shell";
cmd!("echo Hello rust {}!", name).run().unwrap();
// Extract environment variable
cmd!("echo HOME is $HOME").run().unwrap();
ShellResult
The return value of ShellCommand#run()
is ShellResult
which is Ok(_)
only when the command successfully runs and its execution code is 0, so you
can use ?
operator to check if the command successfully exits or not.
#[macro_use] extern crate shell;
use shell::ShellResult;
fn shell_function() -> ShellResult {
cmd!("echo Command A").run()?;
cmd!("echo Command B").run()?;
shell::ok()
}
Output string
ShellCommand has a shorthand to obtain stdout as UTF8 string.
#[macro_use] extern crate shell;
assert_eq!(cmd!("echo OK").stdout_utf8().unwrap(), "OK\n");
Spawn
ShellCommand has spawn()
method which runs the command asynchronously and
returns ShellChild
.
#[macro_use] extern crate shell;
extern crate libc;
use shell::ShellResultExt;
// Wait
let child = cmd!("sleep 2").spawn().unwrap();
child.wait().unwrap();
// Signal
let child = cmd!("sleep 2").spawn().unwrap();
child.signal(libc::SIGINT);
let result = child.wait();
assert!(result.is_err(), "Should be error as it exits with a signal");
assert!(result.status().is_ok(), "Still able to obtain status");
Thread
If you would like to run a sequence of commands asynchronously,
shell::spawn
creates a thread as well as std::thread::spawn
but it
returns ShellHandle
wrapping std::thread::JoinHandle
.
ShellHandle#signal()
is used to send a signal to processes running on the
thread. It also stops launching a new process by ShellComamnd::run()
on
that thread.
#[macro_use] extern crate shell;
extern crate libc;
use shell::ShellResult;
use shell::ShellResultExt;
let handle = shell::spawn(|| -> ShellResult {
cmd!("sleep 3").run()
});
handle.signal(libc::SIGINT);
let result = handle.join().unwrap();
assert!(result.is_err(), "Should be error as it exits with a signal");
assert!(result.status().is_ok(), "Still able to obtain status");
Signal handling
trap_signal_and_wait_children()
starts watching SIGINT and SIGTERM, and
waits all child processes before exiting the process when receiving these
signals. The function needs to be called before launching any new thread.
extern crate shell;
shell::trap_signal_and_wait_children().unwrap();
Access underlaying objects
ShellComamnd
wraps std::process::Command
and ShellChild
wraps
std::process::Child
. Both underlaying objects are accessible via public
fields.
#[macro_use] extern crate shell;
use std::process::Stdio;
use std::io::Read;
// Access std::process::Command.
let mut shell_command = cmd!("echo OK");
{
let mut command = &mut shell_command.command;
command.stdout(Stdio::piped());
}
// Access std::process::Child.
let shell_child = shell_command.spawn().unwrap();
{
let mut lock = shell_child.0.write().unwrap();
let mut child = &mut lock.as_mut().unwrap().child;
let mut str = String::new();
child.stdout.as_mut().unwrap().read_to_string(&mut str);
}
shell_child.wait().unwrap();
License
Apatch 2 License
Macros
format
and args
Structs
ShellChildArc
and provides helper functions.Enums
Traits
Functions
format
and args
.
The function is invoked from cmd!
macro internally.ShellResult
which is Ok
.Type Definitions
ShellChildCore
.