du: use multi-line strings and print the actual name, not a literal du.

du/du.rs

@@ -155,24 +155,28 @@ fn main() {
     };
 
     if matches.opt_present("help") {
-        println!("du {} - estimate file space usage", VERSION);
+        println!("{program} {version} - estimate file space usage
-        println!("");
+
-        println!("Usage:");
+Usage
-        println!("  {0:s} [OPTION]... [FILE]...", program);
+  {program} [OPTION]... [FILE]...
-        println!("  {0:s} [OPTION]... --files0-from=F", program);
+  {program} [OPTION]... --files0-from=F
-        println!("");
+
-        println!("{}", getopts::usage("Summarize disk usage of each FILE, recursively for directories.", opts));
+{usage}
-        println!("Display  values  are  in  units  of  the  first  available  SIZE from
+
+Display  values  are  in  units  of  the  first  available  SIZE from
 --block-size,  and the DU_BLOCK_SIZE, BLOCK_SIZE and BLOCKSIZE environ‐
 ment variables.  Otherwise, units default to  1024  bytes  (or  512  if
 POSIXLY_CORRECT is set).
 
 SIZE  is  an  integer and optional unit (example: 10M is 10*1024*1024).
 Units are K, M, G, T, P, E, Z, Y (powers of 1024) or KB, MB, ...  (pow‐
-ers of 1000).");
+ers of 1000).",
+                 program = program,
+                 version = VERSION,
+                 usage = getopts::usage("Summarize disk usage of each FILE, recursively for directories.", opts));
         return
     } else if matches.opt_present("version") {
-        println!("du version: {}", VERSION);
+        println!("{} version: {}", program, VERSION);
         return
     }
 
@@ -205,11 +209,11 @@ ers of 1000).");
 
     let MB = match matches.opt_present("si") {
         true => 1000 * 1000,
-        false => 1024 * 1024,  
+        false => 1024 * 1024,
     };
     let KB = match matches.opt_present("si") {
         true => 1000,
-        false => 1024,  
+        false => 1024,
     };
 
     let block_size = match matches.opt_str("block-size") {
@@ -220,7 +224,7 @@ ers of 1000).");
             let mut letters = ~[];
             for c in s.chars() {
                 if found_letter && c.is_digit() || !found_number && !c.is_digit() {
-                    println!("du: invalid --block-size argument '{}'", s);
+                    println!("{}: invalid --block-size argument '{}'", program, s);
                     return
                 } else if c.is_digit() {
                     found_number = true;
@@ -243,7 +247,7 @@ ers of 1000).");
                 "ZB" => 1000 * 1000 * 1000 * 1000 * 1000 * 1000 * 1000,
                 "YB" => 1000 * 1000 * 1000 * 1000 * 1000 * 1000 * 1000 * 1000,
                 _ => {
-                    println!("du: invalid --block-size argument '{}'", s); return
+                    println!("{}: invalid --block-size argument '{}'", program, s); return
                 }
             };
             number * multiple
@@ -276,13 +280,12 @@ ers of 1000).");
                 "long-iso" => "%Y-%m-%d %H:%M",
                 "iso" => "%Y-%m-%d",
                 _ => {
-                    println!("
+                    println!("{program}: invalid argument '{}' for 'time style'
-du: invalid argument 'awdwa' for 'time style'
 Valid arguments are:
 - 'full-iso'
 - 'long-iso'
 - 'iso'
-Try 'du --help' for more information.");
+Try '{program} --help' for more information.", s, program = program);
                     return
                 }
             }
@@ -318,10 +321,10 @@ Try 'du --help' for more information.");
                                 "created" => stat.created,
                                 "modified" => stat.modified,
                                 _ => {
-                                    println!("du: invalid argument 'modified' for '--time'
+                                    println!("{program}: invalid argument 'modified' for '--time'
     Valid arguments are:
       - 'accessed', 'created', 'modified'
-    Try 'du --help' for more information.");
+    Try '{program} --help' for more information.", program = program);
                                     return
                                 }
                             },