Refactor yes to remove libc dependency

Yes, using libc while using nix waas a bit redundant.

src/uu/yes/Cargo.toml

@@ -16,11 +16,10 @@ path = "src/yes.rs"
 
 [dependencies]
 clap = { workspace=true }
-libc = { workspace=true }
 uucore = { workspace=true, features=["pipes"] }
 
-[target.'cfg(any(target_os = "linux", target_os = "android"))'.dependencies]
-nix = { workspace=true }
+[target.'cfg(unix)'.dependencies]
+nix = { workspace=true, features = ["signal"] }
 
 [[bin]]
 name = "yes"

src/uu/yes/src/yes.rs

@@ -11,6 +11,8 @@ use std::borrow::Cow;
 use std::io::{self, Result, Write};
 
 use clap::{Arg, ArgAction, Command};
+#[cfg(unix)]
+use nix::sys::signal::{signal, SigHandler::SigDfl, Signal::SIGPIPE};
 use uucore::error::{UResult, USimpleError};
 use uucore::{format_usage, help_about, help_usage};
 
@@ -71,11 +73,11 @@ fn prepare_buffer<'a>(input: &'a str, buffer: &'a mut [u8; BUF_SIZE]) -> &'a [u8
 
 #[cfg(unix)]
 fn enable_pipe_errors() -> Result<()> {
- let ret = unsafe { libc::signal(libc::SIGPIPE, libc::SIG_DFL) };
- if ret == libc::SIG_ERR {
- return Err(io::Error::new(io::ErrorKind::Other, ""));
+ // SAFETY: this function is safe as long as we do not use a custom SigHandler -- we use the default one.
+ match unsafe { signal(SIGPIPE, SigDfl) } {
+ Ok(_) => Ok(()),
+ _ => Err(io::Error::new(io::ErrorKind::Other, "")),
  }
- Ok(())
 }
 
 #[cfg(not(unix))]