Availability:C-language interface function
int PL_action(int,
...)Perform some action on the Prolog system. int describes the
action. Remaining arguments depend on the requested action. The actions
are listed below:
- PL_ACTION_TRACE
- Start Prolog tracer (trace/0).
Requires no arguments.
- PL_ACTION_DEBUG
- Switch on Prolog debug mode (debug/0).
Requires no arguments.
- PL_ACTION_BACKTRACE
- Print backtrace on current output stream. The argument (an
int
)
is the number of frames printed.
- PL_ACTION_HALT
- Halt Prolog execution. This action should be called rather than Unix
exit() to give Prolog the opportunity to clean up. This call does
not return. The argument (an
int
) is the exit code. See halt/1.
- PL_ACTION_ABORT
- Generate a Prolog abort (abort/0).
This call does not return. Requires no arguments.
- PL_ACTION_BREAK
- Create a standard Prolog break environment (break/0).
Returns after the user types the end-of-file character. Requires no
arguments.
- PL_ACTION_GUIAPP
- Windows: Used to indicate to the kernel that the application is a GUI
application if the argument is not 0, and a console application if the
argument is 0. If a fatal error occurs, the system uses a windows
messagebox to report this on a GUI application, and otherwise simply
prints the error and exits.
- PL_ACTION_TRADITIONAL
- Same effect as using --traditional. Must be called
before PL_initialise().
- PL_ACTION_WRITE
- Write the argument, a
char *
to the current output stream.
- PL_ACTION_FLUSH
- Flush the current output stream. Requires no arguments.
- PL_ACTION_ATTACH_CONSOLE
- Attach a console to a thread if it does not have one. See
attach_console/0.
- PL_GMP_SET_ALLOC_FUNCTIONS
- Takes an integer argument. If
TRUE
, the GMP allocations are
immediately bound to the Prolog functions. If FALSE
,
SWI-Prolog will never rebind the GMP allocation functions. See
mp_set_memory_functions() in the GMP documentation. The action
returns
FALSE
if there is no GMP support or GMP is already
initialised.