Applications are window-based programs that have an XView format icon associated with them.
Utilities are nonwindow-based programs that run in a text window.
The new program must be included in the user's path. Commas separate items for multiple arguments. Nonwindow applications are similar, except that the image name is replaced with a short description of the format. Spaces in this description are replaced with commas, which are replaced by spaces when xtalmgr loads the file. Your program can be either in C or Fortran.