Next: Initialization, Up: Part V Overview of Main Functions [Contents][Index]

### 32.1 Version Information

The header file `forms.h` defines three symbolic constants which you can use to conditionally compile your application. They are

`FL_VERSION`

  The major version number.

`FL_REVISION`

  Revision number.

`FL_INCLUDE_VERSION`

  `1000 * FL_VERSION + FL_REVISION`

There is also a routine that can be used to obtain the library version at run time:

    int fl_library_version(int *version, int *revision)

The function returns a consolidated version information, computed as `1000 * version + revision`. For example, for library version 1 revision 21 (1.21), the function returns a value of 1021 with `version` and `revision` (if not `NULL`) set to 1 and 21, respectively.

It is always a good idea to check if the header and the run time library are of the same version and take appropriate actions when they are not. This is especially important for versions less than 1.

To obtain the version number of the library used in an executable, run the command with `-flversion` option, which will print the complete version information.