gui: Implement descriptive tree items.

[gsu.git] / README.md

diff --git a/README.md b/README.md
index 81768f5aec5ee8dbab1bb952a9d282ce49a688cc..f08718c3a1d6d57fde03babb18f3056b8a79401e 100644 (file)
--- a/README.md
+++ b/README.md
@@ -431,23 +431,27 @@ contents of the kernel log buffer. Bash code which defines the menu
 tree could look like this:
 
                menu_tree='
-                       load_average
-                       processes
-                       hardware/
-                               cpu
-                               scsi
-                       storage/
-                               df
-                               mdstat
-                       log/
-                               syslog
-                               dmesg
+                       load_average System load
+                       processes Running processes of a user
+                       hardware/ Hardware related information
+                               cpu Show prozessor type and features
+                               scsi Show SCSI devices
+                       storage/ Filesystems and software raid
+                               df List of mounted filesystems
+                               mdstat Status of software raid arrays
+                       log/ System and kernel logs
+                               syslog System log
+                               dmesg Kernel log
                '
 
-In this tree, `hardware/`, `block_devices/` and `log/` are the only
-internal nodes. Note that these are written with a trailing slash
-character while the leaf nodes have no slash at the end. All entries
-of the menu tree must be indented by tab characters.
+Each line of the menu tree consists of an identifier, suffixed with an
+optional slash, and a description. The identifier becomes part of the
+name of a bash function and should only contain alphabetic characters
+and underscores. The description becomes the text shown as the menu
+item. Identifiers suffixed with a slash are regarded as internal nodes
+which represent submenus. In the above tree, `hardware/`, `storage/`
+and `log/` are internal nodes. All entries of the menu tree must be
+properly indented by tab characters.
 
 ___Action handlers___
 
@@ -463,7 +467,7 @@ handler for the `df` node:
                }
 
 The function name `lsi_df` is derived from the name of the script
-(`lsi`) and the name of the leaf node (`df`). The function simply
+(`lsi`) and the identifier of the leaf node (`df`). The function simply
 passes the output of the `df(1)` command as the first argument to the
 public gsu function `gsu_msgbox()` which runs dialog(1) to display
 a message box that shows the given text.
@@ -496,24 +500,24 @@ to do is to source the gsu gui module and to call `gsu_gui()`:
 
 ___Example___
 
-The complete lsi script below can be used as a starting point
-for your own gsu gui application. If you cut and paste it, be
-sure to not turn tab characters into space characters.
+The complete lsi script below can be used as a starting point for your
+own gsu gui application. If you cut and paste it, be sure to not turn
+tab characters into space characters. The script must be named "lsi".
 
                #!/bin/bash
 
                menu_tree='
-                       load_average
-                       processes
-                       hardware/
-                               cpu
-                               scsi
-                       storage/
-                               df
-                               mdstat
-                       log/
-                               syslog
-                               dmesg
+                       load_average System load
+                       processes Running processes of a user
+                       hardware/ Hardware related information
+                               cpu Show prozessor type and features
+                               scsi Show SCSI devices
+                       storage/ Filesystems and software raid
+                               df List of mounted filesystems
+                               mdstat Status of software raid arrays
+                       log/ System and kernel logs
+                               syslog System log
+                               dmesg Kernel log
                '
 
                lsi_load_average()
@@ -651,6 +655,13 @@ following two statements are equivalent
 If an option is set both in the environment and in the config file,
 the environment takes precedence.
 
+The `$gsu_config_file` variable can actually contain more than one
+filename, separated by spaces. The config files are processed in
+order, so that an option that is specified in the second config file
+overwrites the definition given in the first. This is useful for
+applications which implement a system-wide config file in addition
+to a per-user config file.
+
 ___Checking config options___
 
 The gsu config module defines two public functions for this purpose:
@@ -727,3 +738,4 @@ References
 ----------
 - [bash](http://www.gnu.org/software/bash/bash.html)
 - [dialog](http://www.invisible-island.net/dialog/dialog.html)
+- [The author's home page](http://people.tuebingen.mpg.de/maan/)