This library deals with the highly platform specific task of opening a
web page. In addition, is provides a mechanism similar to
absolute_file_name/3 that expands compound terms to concrete URLs. For
example, the SWI-Prolog home page can be opened using:
- Open URL in running version of the users' browser or start a new
browser. This predicate tries the following steps:
- If a prolog flag (see set_prolog_flag/2)
browser is set
and this is the name of a known executable, use this. The
flag may be set to
Command-Mode, where mode is one of
bg, requesting Command to run in foreground or background
mode. Default is
- On Windows, use
- Find a generic `open' comment. Candidates are
- If a environment variable
BROWSER is set
and this is the name of a known executable, use this.
- Try to find a known browser.
@tbd Figure out the right tool in step 3 as it is not
uncommon that multiple are installed.
- run_browser(+Browser, +URL) is det[private]
- Open a page using a browser.
- run_command(+Command, +Args, +Background)[private]
- Run OS command Command using Args, silencing the error output
because many browsers are rather verbose.
- known_browser(+FileBaseName, -Compatible)[multifile]
- True if browser FileBaseName has a remote protocol compatible to
- Succeeds if Command is in $PATH. Works for Unix systems. For
Windows we have to test for executable extensions.
- url_path(+Alias, -Expansion) is nondet[private]
- Define URL path aliases. This multifile predicate is defined in
user. Expansion is either a URL, or a term Alias(Sub).
- expand_url_path(+Spec, -URL)
- Expand URL specifications similar to absolute_file_name/3. The
predicate url_path/2 plays the role of file_search_path/2.
existence_error(url_path, Spec) if the location is not