initial commit for github

doc/input/ddl_generators.md

@@ -0,0 +1,77 @@
+# DDL Generators (ddl2header, header2ddl) {#page_ddl_generators}
+
+ddl2header and header2ddl are command line utilites to automatically generate 
+C/C++ header files from DDL desriptions and vice versa.
+
+# Usage
+
+## ddl2header
+
+````
+ddl2header [options]
+
++++++++++++++++++++++++++++++
++++ Command line option:  +++
++++++++++++++++++++++++++++++
+
+To create a header file from an existing description file. You have to set the
+following options:
+
+ -headerfile=<PATH>                  - [Mandatory] The path to the header
+                                         file (target).
+
+ -descriptionfile=<PATH>             - [Mandatory] The path to the description
+                                         file (source).
+
+ -struct=<StructNameInHeader>        - [Optional] Just create the header
+                                         file for the given struct
+                                         of the description file.
+
+++++++++++++++++
++++ Example  +++
+++++++++++++++++
+-headerfile=c:/myHeaderFile.h -descriptionfile=c:/myDescriptionFile.description
+or-headerfile=c:/myHeaderFile.h -descriptionfile=c:/myDescriptionFile.description -struct=
+tMyStruct
+````
+
+## header2ddl
+
+````
+header2ddl [options]
+
++++++++++++++++++++++++++++++
++++ Command line option:  +++
++++++++++++++++++++++++++++++
+
+To create a header file from an existing description file. You have to set the
+following options:
+
+ -headerfile=<PATH>                  - [Mandatory] The path to the header
+                                         file (source).
+
+ -descriptionfile=<PATH>             - [Mandatory] The path to the description
+                                         file (target).
+
+ -struct=<StructNameInHeader>        - [Optional] Just create the description
+                                         file for the given struct
+                                         of the header file.
+
+ -ddlversion=<VersionOfDDLFile>        - [Optional] Default value is ddl4.
+                                         Supported formats are
+                                         3.0 and 4.0
+
+++++++++++++++++
++++ Example  +++
+++++++++++++++++
+-headerfile=c:/myHeaderFile.h -descriptionfile=c:/myDescriptionFile.description
+or-headerfile=c:/myHeaderFile.h -descriptionfile=c:/myDescriptionFile.description -struct=
+tMyStruct
+````
+
+## Notes
+
+- Target files are never just overwritten (independent of conversion direction). 
+If the target file exists the generators will try to merge the contents of source and target.  
+**Warning:** If the target file contains content that can not be parsed by the ddl library
+it might be missing from the result file. **Keep a backup!**