the system initialisation, the system consults (see consult/1)
the user's init file. This file is searched using
using the path alias (see file_search_path/2)
app_config. This is a directory named
below the OS default name for placing application configuration data:
- On Windows, the CSIDL folder
C:\Documents and Settings\username\Application Data.
- If the environment variable
XDG_DATA_HOME is set, use
this. This follows the free
- The expansion of
The directory can be found using this call:
?- absolute_file_name(app_config(.), Dir, [file_type(directory)]).
Dir = '/home/jan/.config/swi-prolog'.
After the first startup file is found it is loaded and Prolog stops
looking for further startup files. The name of the startup file can be
changed with the‘-f file’option.
If File denotes an absolute path, this file is loaded,
otherwise the file is searched for using the same conventions as for the
default startup file. Finally, if file is
none, no file is loaded.
The installation provides a file
(commented) commands that are often used to customize the behaviour of
Prolog, such as interfacing to the editor, color selection or history
parameters. Many of the development tools provide menu entries for
editing the startup file and starting a fresh startup file from the
See also the -s (script) and -F
(system-wide initialisation) in section
2.4 and section 2.3.