The Bell character ( english Bell - Bell, abbreviated: BEL) is a control character and has the numerical value in the ASCII 7 (hexadecimal 0x07 ) and in EBCDIC the numeric value 47 (hexadecimal 0x2F ). When it is sent to a printer or a terminal, nothing is displayed, but an audible signal. Window of terminal emulators usually flash briefly to indicate to the user where the alarm signal is issued.
A Bell character exists in the Baudot code, where it was used by no later than 1901 ( code 01011 in Baudot - Murray code, CCITT -2) for the Telegraph. Should send a Bell character the attention of the authorities responsible for the Telegraph at the other end of the line excite people.
In C-like programming the Bell character is often expressed using the escape sequence \ a ( for alert ( alarm) or audible ( sound) ). There are Unicode block " Control Pictures " (Control Pictures) a sign for the visual representation of the Bell character, symbol for bell, U 2407 ( ␇ ), although not with the actual Bell characters in Unicode block " Basic Latin " ( Basic Latin), U 0007, may be confused.
In the command line of Microsoft Windows, PC -DOS and MS- DOS, or in any Unix-like shell, the user can enter the echo command, followed by Ctrl G, as the
Is displayed. After the confirmation of the command by pressing the Enter key on the computer outputs a beep.
- Control character