Re: sh compatibility issue

[Peter Stephenson <p.w.stephenson@xxxxxxxxxxxx>]

On Fri, 4 Mar 2011 14:36:34 +0100
Jilles Tjoelker <jilles@xxxxxxxx> wrote:
> Although 'command' is often implemented as some sort of precommand
> modifier, the POSIX specification says it is a regular builtin,
> therefore redirection errors are not fatal (and variable assignments do
> not persist). The specification also says that 'command' causes operand
> (syntax) errors to be non-fatal.

This should fix at least some such problems.

Index: Src/exec.c
===================================================================
RCS file: /cvsroot/zsh/zsh/Src/exec.c,v
retrieving revision 1.191
diff -p -u -r1.191 exec.c
--- Src/exec.c	23 Feb 2011 09:47:06 -0000	1.191
+++ Src/exec.c	6 Mar 2011 20:25:15 -0000
@@ -2324,7 +2324,7 @@ execcmd(Estate state, int input, int out
     int nullexec = 0, assign = 0, forked = 0;
     int is_shfunc = 0, is_builtin = 0, is_exec = 0, use_defpath = 0;
     /* Various flags to the command. */
-    int cflags = 0, checked = 0, oautocont = -1;
+    int cflags = 0, orig_cflags = 0, checked = 0, oautocont = -1;
     LinkList redir;
     wordcode code;
     Wordcode beg = state->pc, varspc;
@@ -2416,6 +2416,7 @@ execcmd(Estate state, int input, int out
 		checked = !(cflags & BINF_BUILTIN);
 		break;
 	    }
+	    orig_cflags |= cflags;
 	    cflags &= ~BINF_BUILTIN & ~BINF_COMMAND;
 	    cflags |= hn->flags;
 	    if (!(hn->flags & BINF_PREFIX)) {
@@ -3298,11 +3299,13 @@ execcmd(Estate state, int input, int out
 
  done:
     if (isset(POSIXBUILTINS) &&
-	(cflags & (BINF_PSPECIAL|BINF_EXEC))) {
+	(cflags & (BINF_PSPECIAL|BINF_EXEC)) &&
+	!(orig_cflags & BINF_COMMAND)) {
 	/*
 	 * For POSIX-compatible behaviour with special
 	 * builtins (including exec which we don't usually
 	 * classify as a builtin) we treat all errors as fatal.
+	 * The "command" builtin is not special so resets this behaviour.
 	 */
 	if (redir_err || errflag) {
 	    if (!isset(INTERACTIVE)) {
Index: Test/A04redirect.ztst
===================================================================
RCS file: /cvsroot/zsh/zsh/Test/A04redirect.ztst,v
retrieving revision 1.17
diff -p -u -r1.17 A04redirect.ztst
--- Test/A04redirect.ztst	22 Feb 2011 20:09:20 -0000	1.17
+++ Test/A04redirect.ztst	6 Mar 2011 20:25:15 -0000
@@ -386,6 +386,13 @@
 ?zsh:2: no such file or directory: /nonexistent/nonexistent
 
   $ZTST_testdir/../Src/zsh -f -o POSIX_BUILTINS -c '
+  command set >/nonexistent/nonexistent
+  echo output'
+0:failed special builtin redir with command prefix, POSIX_BUILTINS
+>output
+?zsh:2: no such file or directory: /nonexistent/nonexistent
+
+  $ZTST_testdir/../Src/zsh -f -o POSIX_BUILTINS -c '
   echo >/nonexistent/nonexistent
   echo output'
 0:failed unspecial builtin redir, POSIX_BUILTINS

-- 
Peter Stephenson <p.w.stephenson@xxxxxxxxxxxx>
Web page now at http://homepage.ntlworld.com/p.w.stephenson/