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#undef

The #undef directive is used to remove values defined by #define directives from the defined substitution list.

/* undef_example.inp */
#define ATEST 1000
atest is defined to be equal to ATEST
#undef ATEST
ATEST is no longer defined
evaluates to
atest is defined to be equal to 1000
ATEST is no longer defined



Jeff Siebers X88554
Mon Apr 21 09:12:07 PDT 1997