The and Preprocessor Operators


The #undef directive removes a previously defined macro name. The general form is

#undef macro-name

For example, in the following code,

#define LEN 100 #define WIDTH 100 char array[LEN][WIDTH]; #undef LEN #undef WIDTH /* at this point both LEN and WIDTH are    undefined */

both LEN and WIDTH are defined until the #undef statements are encountered.

C(s)C++ Programmer's Reference
C Programming on the IBM PC (C Programmers Reference Guide Series)
ISBN: 0673462897
EAN: 2147483647
Year: 2002
Pages: 539 © 2008-2017.
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