C pointer question, dereferencing crash

Posted by skynorth on Stack Overflow See other posts from Stack Overflow or by skynorth
Published on 2010-05-23T22:05:19Z Indexed on 2010/05/23 22:10 UTC
Read the original article Hit count: 175

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c

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pointers

Why do this work?

    int *var;

while(scanf("%d", &var) && *var != 0)
        printf("%d \n", var);

While this does not?

    int *var;

while(scanf("%d", &var) && var != 0)
    printf("%d \n", var);

Doesn't * (dereference operator) give you the value pointed by the pointer? So why does *var != 0 crash the program, while var != 0 does not?

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C pointer question, dereferencing crash - Developer IT

C pointer question, dereferencing crash

c

pointers

Related posts about c

Related posts about pointers

C++ smart pointers: sharing pointers vs. sharing data

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