nc

无需 std 或 libc 直接访问系统调用。

• 文档
• 发行说明

功能

• 无需glibc或musl
• 通过汇编直接访问syscalls
• 没有全局errno变量，每个函数返回errno
• 支持最新的内核API，如linux 5.0+中引入的io-uring和pidfd

使用方法

将此添加到 Cargo.toml

[dependencies]
nc = "0.9"

示例

获取文件状态

let mut statbuf = nc::stat_t::default();
match unsafe { nc::stat("/etc/passwd", &mut statbuf) } {
    Ok(_) => println!("s: {:?}", statbuf),
    Err(errno) => eprintln!("Failed to get file status, got errno: {}", errno),
}

获取可读的错误字符串

let errno = nc::EPERM;
println!("err: {:?}", nc::strerror(errno);

创建进程

let pid = unsafe { nc::fork() };
match pid {
    Ok(0) => {
        println!("child process");
        let args = ["ls", "-l", "-a"];
        let env = ["FOO=BAR"];
        match unsafe { nc::execve("/bin/ls", &args, &env) } {
            Ok(_) => {},
            Err(errno) => eprintln!("`ls` got err: {}", errno),
        }
    }
    Ok(pid) => println!("[parent] child pid: {pid} "),
    Err(errno) => eprintln!("errno: {}", errno),
}

杀死自身

let pid = unsafe { nc::getpid() };
let ret = unsafe { nc::kill(pid, nc::SIGTERM) };
// Never reach here.
println!("ret: {:?}", ret);

或处理信号

fn handle_alarm(signum: i32) {
    assert_eq!(signum, nc::SIGALRM);
}

fn main() {
    #[cfg(nc_has_sa_restorer)]
    let sa = nc::sigaction_t {
        sa_handler: handle_alarm as nc::sighandler_t,
        sa_flags: nc::SA_RESTORER | nc::SA_RESTART,
        sa_restorer: nc::restore::get_sa_restorer(),
        ..nc::sigaction_t::default()
    };
    #[cfg(not(nc_has_sa_restorer))]
    let sa = nc::sigaction_t {
        sa_handler: handle_alarm as nc::sighandler_t,
        sa_flags: nc::SA_RESTART,
        ..nc::sigaction_t::default()
    };
    let ret = unsafe { nc::rt_sigaction(nc::SIGALRM, Some(&sa), None) };
    assert!(ret.is_ok());
    let remaining = unsafe { nc::alarm(1) };
    let mask = nc::sigset_t::default();
    let ret = unsafe { nc::rt_sigsuspend(&mask) };
    assert!(ret.is_err());
    assert_eq!(ret, Err(nc::EINTR));
    assert_eq!(remaining, Ok(0));
}

支持的操作系统和架构

• linux
  • aarch64
  • arm
  • loongarch64
  • mips
  • mips64
  • mips64el
  • mipsel
  • powerpc64
  • powerpc64el
  • riscv64
  • s390x
  • x86
  • x86-64
• android
  • aarch64
• freebsd
  • x86-64
• netbsd
  • x86-64
• mac os
  • x86-64

相关项目

• nix
• syscall
• relibc
• Linux 系统调用支持
• golang中的syscall pkg

许可

此库受Apache-2.0 许可证管辖。