1 files changed, 37 insertions, 19 deletions
diff --git a/src/cmd/nm/doc.go b/src/cmd/nm/doc.go
index 8e88e2e63..b62da47c0 100644
--- a/src/cmd/nm/doc.go
+++ b/src/cmd/nm/doc.go
@@ -1,23 +1,41 @@
-// Copyright 2009 The Go Authors. All rights reserved.
+// Copyright 2013 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build ignore
-
-/*
-
-Nm is a version of the Plan 9 nm command.  The original is documented at
-
-	http://plan9.bell-labs.com/magic/man2html/1/nm
-
-It prints the name list (symbol table) for programs compiled by gc as well as the
-Plan 9 C compiler.
-
-This implementation adds the flag -S, which prints each symbol's size
-in decimal after its address.
-
-Usage:
-	go tool nm [-aghnsSTu] file
-
-*/
+// Nm lists the symbols defined or used by an object file, archive, or executable.
+//
+// Usage:
+//	go tool nm [options] file...
+//
+// The default output prints one line per symbol, with three space-separated
+// fields giving the address (in hexadecimal), type (a character), and name of
+// the symbol. The types are:
+//
+//	T	text (code) segment symbol
+//	t	static text segment symbol
+//	R	read-only data segment symbol
+//	r	static read-only data segment symbol
+//	D	data segment symbol
+//	d	static data segment symbol
+//	B	bss segment symbol
+//	b	static bss segment symbol
+//	C	constant address
+//	U	referenced but undefined symbol
+//
+// Following established convention, the address is omitted for undefined
+// symbols (type U).
+//
+// The options control the printed output:
+//
+//	-n
+//		an alias for -sort address (numeric),
+//		for compatibility with other nm commands
+//	-size
+//		print symbol size in decimal between address and type
+//	-sort {address,name,none,size}
+//		sort output in the given order (default name)
+//		size orders from largest to smallest
+//	-type
+//		print symbol type after name
+//
 package main