Q42857: C Escape Sequence Like "\n" Doesn’t Function When Passed to C

Article: Q42857
Product(s): See article
Version(s): 4.00 4.00b 4.50
Operating System(s): MS-DOS
Keyword(s): ENDUSER | SR# S890320-23 B_BasicCom | mspl13_basic
Last Modified: 21-DEC-1989

When CALLing a C function from QuickBASIC and passing a C-format
string that contains C escape sequences, the escape sequence does not
execute, but rather displays as part of the string. When the following
example is used, the C "\n" escape sequence for carriage
return/linefeed will not be executed from the C function as expected;
the "\n" will simply be displayed as part of the string:

   FORMAT$ = "number1= %d   number2= %d\n" + CHR$(0)
   CALL CROUTINE(SADD(FORMAT$),LEN(FORMAT$)

This information applies to QuickBASIC Versions 4.00, 4.00b, and 4.50,
to Microsoft BASIC Compiler Versions 6.00 and 6.00b, and to Microsoft
BASIC PDS Version 7.00.

Escape sequences, such as "\n", are replaced with the carriage
return/linefeed characters when the C code is compiled. Therefore, if
they are passed to a C program at run time, "\n" is not recognized as
anything more than part of the string to be displayed.

For the C program to execute an escape sequence passed to it from a
QuickBASIC program, the actual characters for the desired operation
must be appended to the passed string, as in the following example:

FORMAT$ = "number1= d%   number2= d%" + CHR$(13) + CHR$(10) + CHR$(0)
CALL CROUTINE(SADD(FORMAT$),LEN(FORMAT$)

This passes the carriage return/linefeed sequence to the C function.

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