svn commit: r212374 - head/usr.bin/printf

[David O'Brien]

On Thu, Sep 16, 2010 at 09:36:43PM +1000, Bruce Evans wrote:
> On Thu, 16 Sep 2010, David O'Brien wrote:
>> Is a sentence or two a burden to the man page vs. saving someone the time
>> I spent trying to figure out why printf(1) kept throwing up errors?
> 
> WHat about the lesser burder on a character or two for putting -- in the
> synopsis where it is more visible:
> 
> 	printf [--] format [arguments ...]
> 
> POSIX doesn't do this, and it doesn't seem to say anything about the
> problem of a leading - in the format either.  Presumably its general
> utilities specs require _all_ utilities to support "--".

That would be fine for me too, if its prefered that way.

Index: printf.1
===================================================================
--- printf.1	(revision 212773)
+++ printf.1	(working copy)
@@ -43,6 +43,7 @@
 .Nd formatted output
 .Sh SYNOPSIS
 .Nm
+.Op Fl -
 .Ar format Op Ar arguments ...
 .Sh DESCRIPTION
 The
@@ -51,6 +52,13 @@ utility formats and prints its arguments
 of the
 .Ar format .
 The
+.Fl -
+option prevents any interpretation of a leading dash ("-") character in
+.Ar format
+as a
+.Nm
+program option.
+The
 .Ar format
 is a character string which contains three types of objects: plain characters,
 which are simply copied to standard output, character escape sequences which
@@ -355,10 +363,3 @@ Multibyte characters are not recognized 
 a problem if
 .Ql %
 can appear inside a multibyte character).
-.Pp
-Trying to print a dash ("-") as the first character causes
-.Nm
-to interpet the dash as a program argument.
-.Nm --
-must be used before 
-.Ar format .


> I wonder if
> there are any utilities that don't use getopt(3) and as a result aren't
> POSIX conformant since they don't support "--" and also need to support
> a first argument starting with "-" (which won't cause problems because

dd(1) is the only thing coming to mind, but it doesn't need to handle
argments starting with "-".

I believe our find(1) has a problem:

    $ cd /tmp
    $ mkdir ./-
    $ touch ./-/foo
    $ find -- - -name foo
    find -- - -name foo
    usage: find [-H | -L | -P] [-EXdsx] [-f path] path ... [expression]
           find [-H | -L | -P] [-EXdsx] -f path [path ...] [expression]

-- 
-- David  (obrien at FreeBSD.org)