readStream.isRaw#

Aboolean that istrue if the TTY is currently configured to operate as araw device.

This flag is alwaysfalse when a process starts, even if the terminal isoperating in raw mode. Its value will change with subsequent calls tosetRawMode.

readStream.isTTY#

Aboolean that is alwaystrue fortty.ReadStream instances.

readStream.setRawMode(mode)#

• mode<boolean> Iftrue, configures thetty.ReadStream to operate as araw device. Iffalse, configures thetty.ReadStream to operate in itsdefault mode. ThereadStream.isRaw property will be set to the resultingmode.
• Returns:<this> The read stream instance.

Allows configuration oftty.ReadStream so that it operates as a raw device.

When in raw mode, input is always available character-by-character, notincluding modifiers. Additionally, all special processing of characters by theterminal is disabled, including echoing inputcharacters.Ctrl+C will no longer cause aSIGINT whenin this mode.

new tty.ReadStream(fd[, options])#

• fd<number> A file descriptor associated with a TTY.
• options<Object> Options passed to parentnet.Socket,seeoptions ofnet.Socket constructor.
• Returns:<tty.ReadStream>

Creates aReadStream forfd associated with a TTY.

new tty.WriteStream(fd)#

• fd<number> A file descriptor associated with a TTY.
• Returns:<tty.WriteStream>

Creates aWriteStream forfd associated with a TTY.

Event:'resize'#

The'resize' event is emitted whenever either of thewriteStream.columnsorwriteStream.rows properties have changed. No arguments are passed to thelistener callback when called.

process.stdout.on('resize',() => {console.log('screen size has changed!');console.log(`${process.stdout.columns}x${process.stdout.rows}`);});copy

writeStream.clearLine(dir[, callback])#

• dir<number>
  • -1: to the left from cursor
  • 1: to the right from cursor
  • 0: the entire line
• callback<Function> Invoked once the operation completes.
• Returns:<boolean>false if the stream wishes for the calling code to waitfor the'drain' event to be emitted before continuing to write additionaldata; otherwisetrue.

writeStream.clearLine() clears the current line of thisWriteStream in adirection identified bydir.

writeStream.clearScreenDown([callback])#

• callback<Function> Invoked once the operation completes.
• Returns:<boolean>false if the stream wishes for the calling code to waitfor the'drain' event to be emitted before continuing to write additionaldata; otherwisetrue.

writeStream.clearScreenDown() clears thisWriteStream from the currentcursor down.

writeStream.columns#

Anumber specifying the number of columns the TTY currently has. This propertyis updated whenever the'resize' event is emitted.

writeStream.cursorTo(x[, y][, callback])#

• x<number>
• y<number>
• callback<Function> Invoked once the operation completes.
• Returns:<boolean>false if the stream wishes for the calling code to waitfor the'drain' event to be emitted before continuing to write additionaldata; otherwisetrue.

writeStream.cursorTo() moves thisWriteStream's cursor to the specifiedposition.

writeStream.getColorDepth([env])#

• env<Object> An object containing the environment variables to check. Thisenables simulating the usage of a specific terminal.Default:process.env.
• Returns:<number>

Returns:

• 1 for 2,
• 4 for 16,
• 8 for 256,
• 24 for 16,777,216 colors supported.

Use this to determine what colors the terminal supports. Due to the nature ofcolors in terminals it is possible to either have false positives or falsenegatives. It depends on process information and the environment variables thatmay lie about what terminal is used.It is possible to pass in anenv object to simulate the usage of a specificterminal. This can be useful to check how specific environment settings behave.

To enforce a specific color support, use one of the below environment settings.

• 2 colors:FORCE_COLOR = 0 (Disables colors)
• 16 colors:FORCE_COLOR = 1
• 256 colors:FORCE_COLOR = 2
• 16,777,216 colors:FORCE_COLOR = 3

Disabling color support is also possible by using theNO_COLOR andNODE_DISABLE_COLORS environment variables.

writeStream.getWindowSize()#

• Returns:<number[]>

writeStream.getWindowSize() returns the size of the TTYcorresponding to thisWriteStream. The array is of the type[numColumns, numRows] wherenumColumns andnumRows represent the numberof columns and rows in the corresponding TTY.

writeStream.hasColors([count][, env])#

• count<integer> The number of colors that are requested (minimum 2).Default: 16.
• env<Object> An object containing the environment variables to check. Thisenables simulating the usage of a specific terminal.Default:process.env.
• Returns:<boolean>

Returnstrue if thewriteStream supports at least as many colors as providedincount. Minimum support is 2 (black and white).

This has the same false positives and negatives as described inwriteStream.getColorDepth().

process.stdout.hasColors();// Returns true or false depending on if `stdout` supports at least 16 colors.process.stdout.hasColors(256);// Returns true or false depending on if `stdout` supports at least 256 colors.process.stdout.hasColors({TMUX:'1' });// Returns true.process.stdout.hasColors(2 **24, {TMUX:'1' });// Returns false (the environment setting pretends to support 2 ** 8 colors).copy

writeStream.isTTY#

Aboolean that is alwaystrue.

writeStream.moveCursor(dx, dy[, callback])#

• dx<number>
• dy<number>
• callback<Function> Invoked once the operation completes.
• Returns:<boolean>false if the stream wishes for the calling code to waitfor the'drain' event to be emitted before continuing to write additionaldata; otherwisetrue.

writeStream.moveCursor() moves thisWriteStream's cursorrelative to itscurrent position.

writeStream.rows#

Anumber specifying the number of rows the TTY currently has. This propertyis updated whenever the'resize' event is emitted.