grmlzshrc.t2t: Document directory based profiles

diff --git a/doc/grmlzshrc.t2t b/doc/grmlzshrc.t2t
index 82809b2..acb6b23 100644 (file)
--- a/doc/grmlzshrc.t2t
+++ b/doc/grmlzshrc.t2t
@@ -56,6 +56,87 @@ zshs inherit the dirstack of the zsh that most recently updated
 **DIRSTACKFILE**.
 
 == DIRECTORY BASED PROFILES ==
+If you want certain settings to be active in certain directories (and
+automatically switch back and forth between them), this is what you want.
+\
+```
+zstyle ':chpwd:profiles:/usr/src/grml(|/|/*)'   profile grml
+zstyle ':chpwd:profiles:/usr/src/debian(|/|/*)' profile debian
+```
+
+When that's done and you enter a directory that matches the pattern
+in the third part of the context, a function called chpwd_profile_grml,
+for example, is called (if it exists).
+
+If no pattern matches (read: no profile is detected) the profile is
+set to 'default', which means chpwd_profile_default is attempted to
+be called.
+
+A word about the context (the ':chpwd:profiles:*' stuff in the zstyle
+command) which is used: The third part in the context is matched against
+**$PWD**. That's why using a pattern such as /foo/bar(|/|/*) makes sense.
+Because that way the profile is detected for all these values of **$PWD**:
+\
+```
+/foo/bar
+/foo/bar/
+/foo/bar/baz
+```
+
+So, if you want to make double damn sure a profile works in /foo/bar
+and everywhere deeper in that tree, just use (|/|/*) and be happy.
+
+The name of the detected profile will be available in a variable called
+'profile' in your functions. You don't need to do anything, it'll just
+be there.
+
+Then there is the parameter **$CHPWD_PROFILE** which is set to the profile,
+that was active up to now. That way you can avoid running code for a
+profile that is already active, by running code such as the following
+at the start of your function:
+\
+```
+function chpwd_profile_grml() {
+    [[ ${profile} == ${CHPWD_PROFILE} ]] && return 1
+    ...
+}
+```
+
+The initial value for **$CHPWD_PROFILE** is 'default'.
+
+=== Signaling availabily/profile changes ===
+
+If you use this feature and need to know whether it is active in your
+current shell, there are several ways to do that. Here are two simple
+ways:
+
+a) If knowing if the profiles feature is active when zsh starts is
+   good enough for you, you can put the following snippet into your
+   //.zshrc.local//:
+\
+```
+(( ${+functions[chpwd_profiles]} )) &&
+    print "directory profiles active"
+```
+
+b) If that is not good enough, and you would prefer to be notified
+   whenever a profile changes, you can solve that by making sure you
+   start **every** profile function you create like this:
+\
+```
+function chpwd_profile_myprofilename() {
+    [[ ${profile} == ${CHPWD_PROFILE} ]] && return 1
+    print "chpwd(): Switching to profile: $profile"
+  ...
+}
+```
+
+That makes sure you only get notified if a profile is **changed**,
+not everytime you change directory.
+
+=== Version requirement ===
+This feature requires zsh //4.3.3// or newer.
+
 
 == ACCEPTLINE WRAPPER ==