Add noheadings flag to the command

Signed-off-by: Malhar Vora <mlvora.2010@gmail.com>

Author: vbmade2000

src/uu/lsns/src/lsns.rs

@@ -10,7 +10,7 @@ mod errors;
 #[cfg(target_os = "linux")]
 mod smartcols;
 
-use clap::{Command, crate_version};
+use clap::{Arg, ArgAction, Command, crate_version};
 #[cfg(target_os = "linux")]
 use std::ffi::CString;
 #[cfg(target_os = "linux")]
@@ -88,7 +88,10 @@ struct Lsns {
 
 #[uucore::main]
 pub fn uumain(args: impl uucore::Args) -> UResult<()> {
-    let _matches = uu_app().try_get_matches_from(args)?;
+    let matches = uu_app().try_get_matches_from(args)?;
+
+    // Print no headings if this flag is set
+    let noheadings = matches.get_flag("noheadings");
 
     let mut lsns = Lsns {
         processes: Vec::new(),
@@ -110,6 +113,13 @@ pub fn uu_app() -> Command {
         .about(ABOUT)
         .override_usage(format_usage(USAGE))
         .infer_long_args(true)
+        .arg(
+            Arg::new("noheadings")
+                .short('n')
+                .long("noheadings")
+                .action(ArgAction::SetTrue)
+                .help("don't print headings"),
+        )
 }
 
 /// Read information of all the processes from /proc