Terminal Control

The following predicates form a simple access mechanism to the Unix termcap library to provide terminal independant I/O for screen terminals. The library package tty builds on top of these predicates.

tty_get_capability( +Name, +Type, -Result)

  Get the capability named Name from the termcap library. See termcap(5) for the capability names. Type specifies the type of the expected result, and is one of string , number or bool . String results are returned as an atom, number result as an integer and bool results as the atom on or off . If an option cannot be found this predicate fails silently. The results are only computed once. Succesive queries on the same capability are fast.

tty_goto( +X, +Y)

  Goto position (X, Y) on the screen. Note that the predicates line_count/2 and line_position/2 will not have a well defined behaviour while using this predicate.

tty_put( +Atom, +Lines)

  Put an atom via the termcap library function tputs(). This function decodes padding information in the strings returned by tty_get_capability/3 and should be used to output these strings. Lines is the number of lines affected by the operation, or 1 if not applicable (as in almost all cases).

set_tty( -OldStream, +NewStream)

  Set the output stream, used by tty_put/2 and tty_goto/2 to a specific stream. Default is user_output.