diff --git a/ChangeLog b/ChangeLog
index c37b78ed9..faa0f777b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2015-06-29 Peter Stephenson
+
+ * 35655: Doc/Zsh/options.yo, Src/exec.c, Src/options.c,
+ Src/zsh.h: APPEND_CREATE option gives POSIX compatible behaviour
+ for NO_CLOBBER.
+
2015-06-28 Barton E. Schaefer
* 35660: Functions/Prompts/prompt_adam1_setup: avoid perl, fix help
diff --git a/Doc/Zsh/options.yo b/Doc/Zsh/options.yo
index 2371e358c..833c9755e 100644
--- a/Doc/Zsh/options.yo
+++ b/Doc/Zsh/options.yo
@@ -1094,10 +1094,12 @@ pindex(NOCLOBBER)
cindex(clobbering, of files)
cindex(file clobbering, allowing)
item(tt(CLOBBER) (tt(PLUS()C), ksh: tt(PLUS()C)) )(
-Allows `tt(>)' redirection to truncate existing files,
-and `tt(>>)' to create files.
-Otherwise `tt(>!)' or `tt(>|)' must be used to truncate a file,
-and `tt(>>!)' or `tt(>>|)' to create a file.
+Allows `tt(>)' redirection to truncate existing files.
+Otherwise `tt(>!)' or `tt(>|)' must be used to truncate a file.
+
+If the option is not set, and the option tt(APPEND_CREATE) is also
+not set, `tt(>>!)' or `tt(>>|)' must be used to create a file.
+If either option is set, `tt(>>)' may be used.
)
pindex(CORRECT)
pindex(NO_CORRECT)
@@ -1792,6 +1794,21 @@ enditem()
subsect(Shell Emulation)
startitem()
+pindex(APPEND_CREATE
+pindex(NO_APPEND_CREATE)
+pindex(APPENDCREATE)
+pindex(NOAPPENDCREATE)
+cindex(clobbering, POSIX compatibility)
+cindex(file clobbering, POSIX compatibility)
+cindex(no clobber, POSIX compatible)
+item(tt(APPEND_CREATE) )(
+This option only applies when tt(NO_CLOBBER) (-tt(C)) is in effect.
+
+If this option is not set, the shell will report an error when a
+append redirection (tt(>>)) is used on a file that does not already
+exists (the traditional zsh behaviour of tt(NO_CLOBBER)). If the option
+is set, no error is reported (POSIX behaviour).
+)
pindex(BASH_REMATCH)
pindex(NO_BASH_REMATCH)
pindex(BASHREMATCH)
diff --git a/Src/exec.c b/Src/exec.c
index 39d132647..960601f29 100644
--- a/Src/exec.c
+++ b/Src/exec.c
@@ -3315,7 +3315,8 @@ execcmd(Estate state, int input, int output, int how, int last1)
fil = -1;
else if (IS_APPEND_REDIR(fn->type))
fil = open(unmeta(fn->name),
- (unset(CLOBBER) && !IS_CLOBBER_REDIR(fn->type)) ?
+ ((unset(CLOBBER) && unset(APPENDCREATE)) &&
+ !IS_CLOBBER_REDIR(fn->type)) ?
O_WRONLY | O_APPEND | O_NOCTTY :
O_WRONLY | O_APPEND | O_CREAT | O_NOCTTY, 0666);
else
diff --git a/Src/options.c b/Src/options.c
index da3d8308a..1fb102f1d 100644
--- a/Src/options.c
+++ b/Src/options.c
@@ -81,6 +81,7 @@ static struct optname optns[] = {
{{NULL, "allexport", OPT_EMULATE}, ALLEXPORT},
{{NULL, "alwayslastprompt", OPT_ALL}, ALWAYSLASTPROMPT},
{{NULL, "alwaystoend", 0}, ALWAYSTOEND},
+{{NULL, "appendcreate", OPT_EMULATE|OPT_BOURNE}, APPENDCREATE},
{{NULL, "appendhistory", OPT_ALL}, APPENDHISTORY},
{{NULL, "autocd", OPT_EMULATE}, AUTOCD},
{{NULL, "autocontinue", 0}, AUTOCONTINUE},
diff --git a/Src/zsh.h b/Src/zsh.h
index ce9b97903..183620f93 100644
--- a/Src/zsh.h
+++ b/Src/zsh.h
@@ -2120,6 +2120,7 @@ enum {
CHASELINKS,
CHECKJOBS,
CLOBBER,
+ APPENDCREATE,
COMBININGCHARS,
COMPLETEALIASES,
COMPLETEINWORD,