CURS_INITSCR(3CURSES) Curses Library Functions CURS_INITSCR(3CURSES)


NAME


curs_initscr, initscr, newterm, endwin, isendwin, set_term, delscreen -
curses screen initialization and manipulation routines

SYNOPSIS


cc [ flag ... ] file ... -lcurses [ library ... ]
#include <curses.h>

WINDOW *initscr(void);


int endwin(void);


int isendwin(void);


SCREEN *newterm(char *type, FILE *outfd, FILE *infd);


SCREEN *set_term(SCREEN *new);


void delscreen(SCREEN * sp);


DESCRIPTION


initscr() is almost always the first routine that should be called (the
exceptions are slk_init(), filter(), ripoffline(), use_env() and, for
multiple-terminal applications, newterm().) This determines the terminal
type and initializes all curses data structures. initscr() also causes
the first call to refresh() to clear the screen. If errors occur,
initscr() writes an appropriate error message to standard error and
exits; otherwise, a pointer is returned to stdscr(). If the program
needs an indication of error conditions, newterm() should be used instead
of initscr(); initscr() should only be called once per application.


A program that outputs to more than one terminal should use the newterm()
routine for each terminal instead of initscr(). A program that needs an
indication of error conditions, so it can continue to run in a line-
oriented mode if the terminal cannot support a screen-oriented program,
would also use this routine. The routine newterm() should be called once
for each terminal. It returns a variable of type SCREEN * which should be
saved as a reference to that terminal. The arguments are the type of the
terminal to be used in place of $TERM, a file pointer for output to the
terminal, and another file pointer for input from the terminal (if type
is NULL, $TERM will be used). The program must also call endwin() for
each terminal being used before exiting from curses. If newterm() is
called more than once for the same terminal, the first terminal referred
to must be the last one for which endwin() is called.


A program should always call endwin() before exiting or escaping from
curses mode temporarily. This routine restores tty modes, moves the
cursor to the lower left-hand corner of the screen and resets the
terminal into the proper non-visual mode. Calling refresh() or doupdate()
after a temporary escape causes the program to resume visual mode.


The isendwin() routine returns TRUE if endwin() has been called without
any subsequent calls to wrefresh(), and FALSE otherwise.


The set_term() routine is used to switch between different terminals. The
screen reference new becomes the new current terminal. The previous
terminal is returned by the routine. This is the only routine which
manipulates SCREEN pointers; all other routines affect only the current
terminal.


The delscreen() routine frees storage associated with the SCREEN data
structure. The endwin() routine does not do this, so delscreen() should
be called after endwin() if a particular SCREEN is no longer needed.

RETURN VALUES


endwin() returns the integer ERR upon failure and OK upon successful
completion.


Routines that return pointers always return NULL on error.

ATTRIBUTES


See attributes(7) for descriptions of the following attributes:


+---------------+-----------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+-----------------+
|MT-Level | Unsafe |
+---------------+-----------------+

SEE ALSO


curs_kernel(3CURSES), curs_refresh(3CURSES), curs_slk(3CURSES),
curs_util(3CURSES), curses(3CURSES), attributes(7)

NOTES


The header <curses.h> automatically includes the headers <stdio.h> and
<unctrl.h>.


Note that initscr() and newterm() may be macros.


December 31, 1996 CURS_INITSCR(3CURSES)