sh(1): Document 'cd -'.

This reflects the changes in r294649 and can therefore not be MFCed by
itself.

1 files changed, 19 insertions, 6 deletions

diff --git a/bin/sh/sh.1 b/bin/sh/sh.1
index 14ae898..9406779 100644
--- a/bin/sh/sh.1
+++ b/bin/sh/sh.1
@@ -32,7 +32,7 @@
 .\"	from: @(#)sh.1	8.6 (Berkeley) 5/4/95
 .\" $FreeBSD$
 .\"
-.Dd August 29, 2015
+.Dd January 30, 2016
 .Dt SH 1
 .Os
 .Sh NAME
@@ -1952,13 +1952,20 @@ Execute the specified built-in command,
 This is useful when the user wishes to override a shell function
 with the same name as a built-in command.
 .It Ic cd Oo Fl L | P Oc Oo Fl e Oc Op Ar directory
+.It Ic cd Fl
 Switch to the specified
 .Ar directory ,
-or to the directory specified in the
+to the directory specified in the
 .Va HOME
 environment variable if no
 .Ar directory
-is specified.
+is specified or
+to the directory specified in the
+.Va OLDPWD
+environment variable if
+.Ar directory
+is
+.Fl .
 If
 .Ar directory
 does not begin with
@@ -1982,10 +1989,12 @@ the
 .Ic cd
 command will print out the name of the directory
 that it actually switched to
-if this is different from the name that the user gave.
-These may be different either because the
+if the
 .Va CDPATH
-mechanism was used or because a symbolic link was crossed.
+mechanism was used or if
+.Ar directory
+was
+.Fl .
 .Pp
 If the
 .Fl P
@@ -2774,6 +2783,10 @@ Initialization file for interactive shells.
 Locale settings.
 These are inherited by children of the shell,
 and is used in a limited manner by the shell itself.
+.It Ev OLDPWD
+The previous current directory.
+This is used and updated by
+.Ic cd .
 .It Ev PWD
 An absolute pathname for the current directory,
 possibly containing symbolic links.