Using Nonprintable Characters

Some host application models require you to use nonprintable characters within strings. For example, they may be required when waiting for cursor positioning sequences sent from a VT or HP host using the Host Communication string event (WaitForCommString), or sending control sequences via the TransmitANSI command. To represent nonprintable control characters when defining your model in Host Integrator dialog boxes, use the standard C programming convention of encoding each character as a \nnn sequence, where nnn is the octal numeric value of the ASCII character, or use one of the \x sequences that have been defined for the more common control characters. For example, the escape character (0x1B), which prefixes VT cursor positioning sequences, is encoded as \033; carriage returns can be encoded using \r.

When a model file is read by Host Integrator, the \nnn sequences are parsed into their literal nonprintable character equivalents. Because backslashes (\) are interpreted as the beginning of a nonprintable character sequence, Host Integrator represents literal backslashes in strings with two backslashes. For example, if you want to wait for the display string "Enter a backslash (\) to continue" in an operation, what you will see in the Operation Edit dialog box for WaitForDisplayString is "Enter a backslash (\\) to continue". If you modify a model file in XML format or the model file itself, you must follow this syntax to embed literal backslashes within string arguments.

Alphabetic
Sequence
Octal
Equivalent
Also Known As

\a \007 Control-G (BEL) Bell
\b \010 Control-H (BS) Backspace
\t \011 Control-I (TAB) Horizontal tab
\n \012 Control-J (LF) Linefeed
\v \013 Control-K (VT) Vertical tab
\f \014 Control-L (FF) Formfeed
\r \015 Control-M (CR) Carriage return


Related Topics
Bullet Character mode configuration options