zsh-workers/9617

1 files changed, 14 insertions, 3 deletions

diff --git a/Doc/Zsh/redirect.yo b/Doc/Zsh/redirect.yo
index 924b8b64b..bbf8386fe 100644
--- a/Doc/Zsh/redirect.yo
+++ b/Doc/Zsh/redirect.yo
@@ -198,6 +198,8 @@ when tt(MULTIOS) is unset will truncate bar, and write `tt(foo)' into baz.
 sect(Redirections with no command)
 vindex(NULLCMD, use of)
 vindex(READNULLCMD, use of)
+pindex(IGNORE_NULLCMD, use of)
+pindex(SH_NULLCMD, use of)
 If a simple command consists of one or more redirection operators
 and zero or more parameter assignments, but no command name, and the
 parameter tt(NULLCMD) is not set, an error is caused.  If the parameter
@@ -212,6 +214,15 @@ example(< file)
 shows the contents of tt(file) on standard output, with paging if that is a
 terminal.  tt(NULLCMD) and tt(READNULLCMD) may refer to shell functions.
 
-The standard Bourne shell behaviour is obtained by setting tt(NULLCMD) and
-tt(READNULLCMD) to `tt(:)'.  This is the default when zsh is emulating bf(sh)
-or bf(ksh).
+The above default behaviour can be affected by the options
+tt(IGNORE_NULLCMD) and tt(SH_NULLCMD).  tt(SH_NULLCMD) forces the Bourne
+shell behaviour when the parameter tt(NULLCMD) is not set (i.e. the
+implicit command used with the redirections is `tt(:)'), while
+tt(IGNORE_NULLCMD) is used to obtain the same behaviour as if tt(NULLCMD)
+was unset.
+
+The standard Bourne shell behaviour is obtained by setting the options
+tt(IGNORE_NULLCMD) and tt(SH_NULLCMD).  This is the default when zsh is
+emulating bf(sh) or bf(ksh).  The tt(csh) behaviour can be obtained by
+setting only tt(IGNORE_NULLCMD), which is the default when emulating
+bf(csh).