Class: IO

Inherits:
Object
  • Object
show all
Defined in:
(unknown)

Defined Under Namespace

Modules: generic_readable Classes: ConsoleMode

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.console ⇒ #<File:/dev/tty .console(sym, *args) ⇒ Object

Returns an File instance opened console.

If sym is given, it will be sent to the opened console with args and the result will be returned instead of the console IO itself.

You must require ‘io/console’ to use this method.

Overloads:

  • .console ⇒ #<File:/dev/tty

    Returns ].

    Returns:

    • (#<File:/dev/tty) —

      ]



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# File 'ext/io/console/console.c', line 1442

static VALUE
console_dev(int argc, VALUE *argv, VALUE klass)
{
    VALUE con = 0;
    rb_io_t *fptr;
    VALUE sym = 0;

    rb_check_arity(argc, 0, UNLIMITED_ARGUMENTS);
    if (argc) {
  Check_Type(sym = argv[0], T_SYMBOL);
    }
    if (klass == rb_cIO) klass = rb_cFile;
    if (rb_const_defined(klass, id_console)) {
  con = rb_const_get(klass, id_console);
  if (!RB_TYPE_P(con, T_FILE) ||
      (!(fptr = RFILE(con)->fptr) || GetReadFD(fptr) == -1)) {
      rb_const_remove(klass, id_console);
      con = 0;
  }
    }
    if (sym) {
  if (sym == ID2SYM(id_close) && argc == 1) {
      if (con) {
    rb_io_close(con);
    rb_const_remove(klass, id_console);
    con = 0;
      }
      return Qnil;
  }
    }
    if (!con) {
  VALUE args[2];
#if defined HAVE_TERMIOS_H || defined HAVE_TERMIO_H || defined HAVE_SGTTY_H
# define CONSOLE_DEVICE "/dev/tty"
#elif defined _WIN32
# define CONSOLE_DEVICE "con$"
# define CONSOLE_DEVICE_FOR_READING "conin$"
# define CONSOLE_DEVICE_FOR_WRITING "conout$"
#endif
#ifndef CONSOLE_DEVICE_FOR_READING
# define CONSOLE_DEVICE_FOR_READING CONSOLE_DEVICE
#endif
#ifdef CONSOLE_DEVICE_FOR_WRITING
  VALUE out;
  rb_io_t *ofptr;
#endif
  int fd;

#ifdef CONSOLE_DEVICE_FOR_WRITING
  fd = rb_cloexec_open(CONSOLE_DEVICE_FOR_WRITING, O_RDWR, 0);
  if (fd < 0) return Qnil;
        rb_update_max_fd(fd);
  args[1] = INT2FIX(O_WRONLY);
  args[0] = INT2NUM(fd);
  out = rb_class_new_instance(2, args, klass);
#endif
  fd = rb_cloexec_open(CONSOLE_DEVICE_FOR_READING, O_RDWR, 0);
  if (fd < 0) {
#ifdef CONSOLE_DEVICE_FOR_WRITING
      rb_io_close(out);
#endif
      return Qnil;
  }
        rb_update_max_fd(fd);
  args[1] = INT2FIX(O_RDWR);
  args[0] = INT2NUM(fd);
  con = rb_class_new_instance(2, args, klass);
  GetOpenFile(con, fptr);
  fptr->pathv = rb_obj_freeze(rb_str_new2(CONSOLE_DEVICE));
#ifdef CONSOLE_DEVICE_FOR_WRITING
  GetOpenFile(out, ofptr);
  ofptr->pathv = fptr->pathv;
  fptr->tied_io_for_writing = out;
  ofptr->mode |= FMODE_SYNC;
#endif
  fptr->mode |= FMODE_SYNC;
  rb_const_set(klass, id_console, con);
    }
    if (sym) {
  return rb_f_send(argc, argv, con);
    }
    return con;
}

.default_console_size ⇒ Object

fallback to console window size



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# File 'lib/io/console/size.rb', line 3

def IO.default_console_size
  [
    ENV["LINES"].to_i.nonzero? || 25,
    ENV["COLUMNS"].to_i.nonzero? || 80,
  ]
end

Instance Method Details

#beep ⇒ Object 



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# File 'ext/io/console/console.c', line 979

static VALUE
console_beep(VALUE io)
{
    rb_io_t *fptr;
    int fd;

    GetOpenFile(io, fptr);
    fd = GetWriteFD(fptr);
#ifdef _WIN32
    (void)fd;
    MessageBeep(0);
#else
    if (write(fd, "\a", 1) < 0)
  sys_fail_fptr(fptr);
#endif
    return io;
}

#check_winsize_changed ⇒ Object 



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# File 'ext/io/console/console.c', line 879

static VALUE
console_check_winsize_changed(VALUE io)
{
    rb_io_t *fptr;
    HANDLE h;
    DWORD num;

    GetOpenFile(io, fptr);
    h = (HANDLE)rb_w32_get_osfhandle(GetReadFD(fptr));
    while (GetNumberOfConsoleInputEvents(h, &num) && num > 0) {
  INPUT_RECORD rec;
  if (ReadConsoleInput(h, &rec, 1, &num)) {
      if (rec.EventType == WINDOW_BUFFER_SIZE_EVENT) {
    rb_yield(Qnil);
      }
  }
    }
    return io;
}

#clear_screen ⇒ Object 



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# File 'ext/io/console/console.c', line 1421

static VALUE
console_clear_screen(VALUE io)
{
    console_erase_screen(io, INT2FIX(2));
    console_goto(io, INT2FIX(0), INT2FIX(0));
    return io;
}

#console_mode ⇒ Object

Returns a data represents the current console mode.

You must require ‘io/console’ to use this method.



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# File 'ext/io/console/console.c', line 722

static VALUE
console_conmode_get(VALUE io)
{
    conmode t;
    rb_io_t *fptr;
    int fd;

    GetOpenFile(io, fptr);
    fd = GetReadFD(fptr);
    if (!getattr(fd, &t)) sys_fail_fptr(fptr);

    return conmode_new(cConmode, &t);
}

#console_mode=(mode) ⇒ Object

Sets the console mode to mode.

You must require ‘io/console’ to use this method.



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# File 'ext/io/console/console.c', line 744

static VALUE
console_conmode_set(VALUE io, VALUE mode)
{
    conmode *t, r;
    rb_io_t *fptr;
    int fd;

    TypedData_Get_Struct(mode, conmode, &conmode_type, t);
    r = *t;
    GetOpenFile(io, fptr);
    fd = GetReadFD(fptr);
    if (!setattr(fd, &r)) sys_fail_fptr(fptr);

    return mode;
}

#cooked {|io| ... } ⇒ Object

Yields self within cooked mode.

STDIN.cooked(&:gets)

will read and return a line with echo back and line editing.

You must require ‘io/console’ to use this method.

Yields:

  • (io) 


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# File 'ext/io/console/console.c', line 437

static VALUE
console_cooked(VALUE io)
{
    return ttymode(io, rb_yield, io, set_cookedmode, NULL);
}

#cooked! ⇒ Object

Enables cooked mode.

If the terminal mode needs to be back, use io.cooked { … }.

You must require ‘io/console’ to use this method.



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# File 'ext/io/console/console.c', line 453

static VALUE
console_set_cooked(VALUE io)
{
    conmode t;
    rb_io_t *fptr;
    int fd;

    GetOpenFile(io, fptr);
    fd = GetReadFD(fptr);
    if (!getattr(fd, &t)) sys_fail_fptr(fptr);
    set_cookedmode(&t, NULL);
    if (!setattr(fd, &t)) sys_fail_fptr(fptr);
    return io;
}

#cursor ⇒ Object 



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# File 'ext/io/console/console.c', line 1300

static VALUE
console_cursor_pos(VALUE io)
{
    static const struct query_args query = {"\033[6n", 0};
    VALUE resp = console_vt_response(0, 0, io, &query);
    VALUE row, column, term;
    unsigned int r, c;
    if (!RB_TYPE_P(resp, T_ARRAY) || RARRAY_LEN(resp) != 3) return Qnil;
    term = RARRAY_AREF(resp, 2);
    if (!RB_TYPE_P(term, T_STRING) || RSTRING_LEN(term) != 1) return Qnil;
    if (RSTRING_PTR(term)[0] != 'R') return Qnil;
    row = RARRAY_AREF(resp, 0);
    column = RARRAY_AREF(resp, 1);
    rb_ary_resize(resp, 2);
    r = NUM2UINT(row) - 1;
    c = NUM2UINT(column) - 1;
    RARRAY_ASET(resp, 0, INT2NUM(r));
    RARRAY_ASET(resp, 1, INT2NUM(c));
    return resp;
}

#cursor=(cpos) ⇒ Object 



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# File 'ext/io/console/console.c', line 1377

static VALUE
console_cursor_set(VALUE io, VALUE cpos)
{
    cpos = rb_convert_type(cpos, T_ARRAY, "Array", "to_ary");
    if (RARRAY_LEN(cpos) != 2) rb_raise(rb_eArgError, "expected 2D coordinate");
    return console_goto(io, RARRAY_AREF(cpos, 0), RARRAY_AREF(cpos, 1));
}

#cursor_down(val) ⇒ Object 



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# File 'ext/io/console/console.c', line 1391

static VALUE
console_cursor_down(VALUE io, VALUE val)
{
    return console_move(io, +NUM2INT(val), 0);
}

#cursor_left(val) ⇒ Object 



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# File 'ext/io/console/console.c', line 1397

static VALUE
console_cursor_left(VALUE io, VALUE val)
{
    return console_move(io, 0, -NUM2INT(val));
}

#cursor_right(val) ⇒ Object 



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# File 'ext/io/console/console.c', line 1403

static VALUE
console_cursor_right(VALUE io, VALUE val)
{
    return console_move(io, 0, +NUM2INT(val));
}

#cursor_up(val) ⇒ Object 



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# File 'ext/io/console/console.c', line 1385

static VALUE
console_cursor_up(VALUE io, VALUE val)
{
    return console_move(io, -NUM2INT(val), 0);
}

#echo=(flag) ⇒ Object

Enables/disables echo back. On some platforms, all combinations of this flags and raw/cooked mode may not be valid.

You must require ‘io/console’ to use this method.



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# File 'ext/io/console/console.c', line 612

static VALUE
console_set_echo(VALUE io, VALUE f)
{
    conmode t;
    rb_io_t *fptr;
    int fd;

    GetOpenFile(io, fptr);
    fd = GetReadFD(fptr);
    if (!getattr(fd, &t)) sys_fail_fptr(fptr);
    if (RTEST(f))
  set_echo(&t, NULL);
    else
  set_noecho(&t, NULL);
    if (!setattr(fd, &t)) sys_fail_fptr(fptr);
    return io;
}

#echo? ⇒ Boolean

Returns true if echo back is enabled.

You must require ‘io/console’ to use this method.

Returns:

  • (Boolean) 


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# File 'ext/io/console/console.c', line 638

static VALUE
console_echo_p(VALUE io)
{
    conmode t;
    rb_io_t *fptr;
    int fd;

    GetOpenFile(io, fptr);
    fd = GetReadFD(fptr);
    if (!getattr(fd, &t)) sys_fail_fptr(fptr);
    return echo_p(&t) ? Qtrue : Qfalse;
}

#erase_line(val) ⇒ Object 



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# File 'ext/io/console/console.c', line 1348

static VALUE
console_erase_line(VALUE io, VALUE val)
{
    int mode = mode_in_range(val, 2, "line erase");
    rb_io_write(io, rb_sprintf("\x1b[%dK", mode));
    return io;
}

#erase_screen(val) ⇒ Object 



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# File 'ext/io/console/console.c', line 1356

static VALUE
console_erase_screen(VALUE io, VALUE val)
{
    int mode = mode_in_range(val, 3, "screen erase");
    rb_io_write(io, rb_sprintf("\x1b[%dJ", mode));
    return io;
}

#getch(min: nil, time: nil, intr: nil) ⇒ String

Reads and returns a character in raw mode.

See IO#raw for details on the parameters.

You must require ‘io/console’ to use this method.

Returns:

  • (String) 


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# File 'ext/io/console/console.c', line 507

static VALUE
console_getch(int argc, VALUE *argv, VALUE io)
{
    rawmode_arg_t opts, *optp = rawmode_opt(&argc, argv, 0, 0, &opts);
#ifndef _WIN32
    return ttymode(io, getc_call, io, set_rawmode, optp);
#else
    rb_io_t *fptr;
    VALUE str;
    wint_t c;
    int len;
    char buf[8];
    wint_t wbuf[2];
# ifndef HAVE_RB_IO_WAIT
    struct timeval *to = NULL, tv;
# else
    VALUE timeout = Qnil;
# endif

    GetOpenFile(io, fptr);
    if (optp) {
  if (optp->vtime) {
# ifndef HAVE_RB_IO_WAIT
      to = &tv;
# else
      struct timeval tv;
# endif
      tv.tv_sec = optp->vtime / 10;
      tv.tv_usec = (optp->vtime % 10) * 100000;
# ifdef HAVE_RB_IO_WAIT
      timeout = rb_scheduler_timeout(&tv);
# endif
  }
  switch (optp->vmin) {
    case 1: /* default */
      break;
    case 0: /* return nil when timed out */
      if (optp->vtime) break;
      /* fallthru */
    default:
      rb_warning("min option larger than 1 ignored");
  }
  if (optp->intr) {
# ifndef HAVE_RB_IO_WAIT
      int w = rb_wait_for_single_fd(fptr->fd, RB_WAITFD_IN, to);
      if (w < 0) rb_eof_error();
      if (!(w & RB_WAITFD_IN)) return Qnil;
# else
      VALUE result = rb_io_wait(io, RUBY_IO_READABLE, timeout);
      if (result == Qfalse) return Qnil;
# endif
  }
  else if (optp->vtime) {
      rb_warning("Non-zero vtime option ignored if intr flag is unset");
  }
    }
    len = (int)(VALUE)rb_thread_call_without_gvl(nogvl_getch, wbuf, RUBY_UBF_IO, 0);
    switch (len) {
      case 0:
  return Qnil;
      case 2:
  buf[0] = (char)wbuf[0];
  c = wbuf[1];
  len = 1;
  do {
      buf[len++] = (unsigned char)c;
  } while ((c >>= CHAR_BIT) && len < (int)sizeof(buf));
  return rb_str_new(buf, len);
      default:
  c = wbuf[0];
  len = rb_uv_to_utf8(buf, c);
  str = rb_utf8_str_new(buf, len);
  return rb_str_conv_enc(str, NULL, rb_default_external_encoding());
    }
#endif
}

#getpass(prompt = nil) ⇒ String

Reads and returns a line without echo back. Prints prompt unless it is nil.

The newline character that terminates the read line is removed from the returned string, see String#chomp!.

You must require ‘io/console’ to use this method.

Returns:

  • (String) 


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# File 'ext/io/console/console.c', line 1583

static VALUE
console_getpass(int argc, VALUE *argv, VALUE io)
{
    VALUE str, wio;

    rb_check_arity(argc, 0, 1);
    wio = rb_io_get_write_io(io);
    if (wio == io && io == rb_stdin) wio = rb_stderr;
    prompt(argc, argv, wio);
    str = rb_ensure(getpass_call, io, puts_call, wio);
    return str_chomp(str);
}

#goto(y, x) ⇒ Object 



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# File 'ext/io/console/console.c', line 1321

static VALUE
console_goto(VALUE io, VALUE y, VALUE x)
{
    rb_io_write(io, rb_sprintf("\x1b[%d;%dH", NUM2UINT(y)+1, NUM2UINT(x)+1));
    return io;
}

#goto_column(val) ⇒ Object 



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# File 'ext/io/console/console.c', line 1341

static VALUE
console_goto_column(VALUE io, VALUE val)
{
    rb_io_write(io, rb_sprintf("\x1b[%dG", NUM2UINT(val)+1));
    return io;
}

#iflush ⇒ Object

Flushes input buffer in kernel.

You must require ‘io/console’ to use this method.



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# File 'ext/io/console/console.c', line 910

static VALUE
console_iflush(VALUE io)
{
    rb_io_t *fptr;
    int fd;

    GetOpenFile(io, fptr);
    fd = GetReadFD(fptr);
#if defined HAVE_TERMIOS_H || defined HAVE_TERMIO_H
    if (tcflush(fd, TCIFLUSH)) sys_fail_fptr(fptr);
#endif
    (void)fd;
    return io;
}

#ioflush ⇒ Object

Flushes input and output buffers in kernel.

You must require ‘io/console’ to use this method.



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# File 'ext/io/console/console.c', line 956

static VALUE
console_ioflush(VALUE io)
{
    rb_io_t *fptr;
#if defined HAVE_TERMIOS_H || defined HAVE_TERMIO_H
    int fd1, fd2;
#endif

    GetOpenFile(io, fptr);
#if defined HAVE_TERMIOS_H || defined HAVE_TERMIO_H
    fd1 = GetReadFD(fptr);
    fd2 = GetWriteFD(fptr);
    if (fd2 != -1 && fd1 != fd2) {
  if (tcflush(fd1, TCIFLUSH)) sys_fail_fptr(fptr);
  if (tcflush(fd2, TCOFLUSH)) sys_fail_fptr(fptr);
    }
    else {
  if (tcflush(fd1, TCIOFLUSH)) sys_fail_fptr(fptr);
    }
#endif
    return io;
}

#noecho {|io| ... } ⇒ Object

Yields self with disabling echo back.

STDIN.noecho(&:gets)

will read and return a line without echo back.

You must require ‘io/console’ to use this method.

Yields:

  • (io) 


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# File 'ext/io/console/console.c', line 596

static VALUE
console_noecho(VALUE io)
{
    return ttymode(io, rb_yield, io, set_noecho, NULL);
}

#oflush ⇒ Object

Flushes output buffer in kernel.

You must require ‘io/console’ to use this method.



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# File 'ext/io/console/console.c', line 933

static VALUE
console_oflush(VALUE io)
{
    rb_io_t *fptr;
    int fd;

    GetOpenFile(io, fptr);
    fd = GetWriteFD(fptr);
#if defined HAVE_TERMIOS_H || defined HAVE_TERMIO_H
    if (tcflush(fd, TCOFLUSH)) sys_fail_fptr(fptr);
#endif
    (void)fd;
    return io;
}

#pressed?(k) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'ext/io/console/console.c', line 1199

static VALUE
console_key_pressed_p(VALUE io, VALUE k)
{
    int vk = -1;

    if (FIXNUM_P(k)) {
  vk = NUM2UINT(k);
    }
    else {
  const struct vktable *t;
  const char *kn;
  if (SYMBOL_P(k)) {
      k = rb_sym2str(k);
      kn = RSTRING_PTR(k);
  }
  else {
      kn = StringValuePtr(k);
  }
  t = console_win32_vk(kn, RSTRING_LEN(k));
  if (!t || (vk = (short)t->vk) == -1) {
      rb_raise(rb_eArgError, "unknown virtual key code: % "PRIsVALUE, k);
  }
    }
    return GetKeyState(vk) & 0x80 ? Qtrue : Qfalse;
}

#raw(min: nil, time: nil, intr: nil) {|io| ... } ⇒ Object

Yields self within raw mode, and returns the result of the block.

STDIN.raw(&:gets)

will read and return a line without echo back and line editing.

The parameter min specifies the minimum number of bytes that should be received when a read operation is performed. (default: 1)

The parameter time specifies the timeout in seconds with a precision of 1/10 of a second. (default: 0)

If the parameter intr is true, enables break, interrupt, quit, and suspend special characters.

Refer to the manual page of termios for further details.

You must require ‘io/console’ to use this method.

Yields:

  • (io) 


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# File 'ext/io/console/console.c', line 390

static VALUE
console_raw(int argc, VALUE *argv, VALUE io)
{
    rawmode_arg_t opts, *optp = rawmode_opt(&argc, argv, 0, 0, &opts);
    return ttymode(io, rb_yield, io, set_rawmode, optp);
}

#raw!(min: nil, time: nil, intr: nil) ⇒ IO

Enables raw mode, and returns io.

If the terminal mode needs to be back, use io.raw { ... }.

See IO#raw for details on the parameters.

You must require ‘io/console’ to use this method.

Returns:



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# File 'ext/io/console/console.c', line 409

static VALUE
console_set_raw(int argc, VALUE *argv, VALUE io)
{
    conmode t;
    rb_io_t *fptr;
    int fd;
    rawmode_arg_t opts, *optp = rawmode_opt(&argc, argv, 0, 0, &opts);

    GetOpenFile(io, fptr);
    fd = GetReadFD(fptr);
    if (!getattr(fd, &t)) sys_fail_fptr(fptr);
    set_rawmode(&t, optp);
    if (!setattr(fd, &t)) sys_fail_fptr(fptr);
    return io;
}

#scroll_backward(val) ⇒ Object 



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# File 'ext/io/console/console.c', line 1415

static VALUE
console_scroll_backward(VALUE io, VALUE val)
{
    return console_scroll(io, -NUM2INT(val));
}

#scroll_forward(val) ⇒ Object 



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# File 'ext/io/console/console.c', line 1409

static VALUE
console_scroll_forward(VALUE io, VALUE val)
{
    return console_scroll(io, +NUM2INT(val));
}

#winsize ⇒ Array

Returns console size.

You must require ‘io/console’ to use this method.

Returns:

  • (Array) 


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# File 'ext/io/console/console.c', line 788

static VALUE
console_winsize(VALUE io)
{
    rb_io_t *fptr;
    int fd;
    rb_console_size_t ws;

    GetOpenFile(io, fptr);
    fd = GetWriteFD(fptr);
    if (!getwinsize(fd, &ws)) sys_fail_fptr(fptr);
    return rb_assoc_new(INT2NUM(winsize_row(&ws)), INT2NUM(winsize_col(&ws)));
}

#winsize=(size) ⇒ Object

Tries to set console size. The effect depends on the platform and the running environment.

You must require ‘io/console’ to use this method.



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# File 'ext/io/console/console.c', line 810

static VALUE
console_set_winsize(VALUE io, VALUE size)
{
    rb_io_t *fptr;
    rb_console_size_t ws;
#if defined _WIN32
    HANDLE wh;
    int newrow, newcol;
    BOOL ret;
#endif
    VALUE row, col, xpixel, ypixel;
    const VALUE *sz;
    int fd;
    long sizelen;

    GetOpenFile(io, fptr);
    size = rb_Array(size);
    if ((sizelen = RARRAY_LEN(size)) != 2 && sizelen != 4) {
  rb_raise(rb_eArgError,
     "wrong number of arguments (given %ld, expected 2 or 4)",
     sizelen);
    }
    sz = RARRAY_CONST_PTR(size);
    row = sz[0], col = sz[1], xpixel = ypixel = Qnil;
    if (sizelen == 4) xpixel = sz[2], ypixel = sz[3];
    fd = GetWriteFD(fptr);
#if defined TIOCSWINSZ
    ws.ws_row = ws.ws_col = ws.ws_xpixel = ws.ws_ypixel = 0;
#define SET(m) ws.ws_##m = NIL_P(m) ? 0 : (unsigned short)NUM2UINT(m)
    SET(row);
    SET(col);
    SET(xpixel);
    SET(ypixel);
#undef SET
    if (!setwinsize(fd, &ws)) sys_fail_fptr(fptr);
#elif defined _WIN32
    wh = (HANDLE)rb_w32_get_osfhandle(fd);
#define SET(m) new##m = NIL_P(m) ? 0 : (unsigned short)NUM2UINT(m)
    SET(row);
    SET(col);
#undef SET
    if (!NIL_P(xpixel)) (void)NUM2UINT(xpixel);
    if (!NIL_P(ypixel)) (void)NUM2UINT(ypixel);
    if (!GetConsoleScreenBufferInfo(wh, &ws)) {
  rb_syserr_fail(LAST_ERROR, "GetConsoleScreenBufferInfo");
    }
    ws.dwSize.X = newcol;
    ret = SetConsoleScreenBufferSize(wh, ws.dwSize);
    ws.srWindow.Left = 0;
    ws.srWindow.Top = 0;
    ws.srWindow.Right = newcol-1;
    ws.srWindow.Bottom = newrow-1;
    if (!SetConsoleWindowInfo(wh, TRUE, &ws.srWindow)) {
  rb_syserr_fail(LAST_ERROR, "SetConsoleWindowInfo");
    }
    /* retry when shrinking buffer after shrunk window */
    if (!ret && !SetConsoleScreenBufferSize(wh, ws.dwSize)) {
  rb_syserr_fail(LAST_ERROR, "SetConsoleScreenBufferInfo");
    }
    /* remove scrollbar if possible */
    if (!SetConsoleWindowInfo(wh, TRUE, &ws.srWindow)) {
  rb_syserr_fail(LAST_ERROR, "SetConsoleWindowInfo");
    }
#endif
    return io;
}