# curs_initscr 3x

## NAME

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

## SYNOPSIS

           #include <curses.h>

           WINDOW *initscr(void);
           int endwin(void);
           bool isendwin(void);
           SCREEN *newterm(char *type, FILE *outfd, FILE *infd);
           SCREEN *set_term(SCREEN *new);
           void delscreen(SCREEN* sp);

## DESCRIPTION

           initscr is normally the first curses routine to call  when
           initializing  a program.  A few special routines sometimes
           need to be called before it; these are  slk_init,  filter,
           ripoffline,  use_env.  For multiple-terminal applications,
           newterm may be called before initscr.

           The initscr code determines the terminal type and initial-
           izes  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.

           A  program  that  outputs to more than one terminal should
           use the newterm  routine  for  each  terminal  instead  of
           initscr.  A program that needs to inspect capabilities, so
           it can continue to run in a line-oriented mode if the ter-
           minal cannot support a screen-oriented program, would also
           use newterm.  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 cur-
           rent terminal.  The previous terminal is returned  by  the
           routine.   This  is  the  only  routine  which manipulates
           SCREEN pointers; all other routines affect only  the  cur-
           rent 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 par-
           ticular SCREEN is no longer needed.

## RETURN VALUE

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

           Routines that return pointers always return NULL on error.

## NOTES

           Note that initscr and newterm may be macros.

## PORTABILITY

           These functions are described in the XSI Curses  standard,
           Issue 4.  It specifies that portable applications must not
           call initscr more than once.

           Old versions of curses, e.g., BSD 4.4, may have returned a
           null  pointer  from  initscr  when  an  error is detected,
           rather than exiting.  It is safe but  redundant  to  check
           the return value of initscr in XSI Curses.

## SEE ALSO

           curses(3x),       curs_kernel(3x),       curs_refresh(3x),
           curs_slk(3x), curs_util(3x)