Best way to allocate a struct pointer: malloc or calloc?

This is a discussion on Best way to allocate a struct pointer: malloc or calloc? within the C Programming forums, part of the General Programming Boards category; in C++ I can use: PHP Code: someStruct  * pSs  = new  someStruct ;  But in C, which: PHP Code: someStruct  ...

  1. #1
    Registered User Joelito's Avatar
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    Exclamation Best way to allocate a struct pointer: malloc or calloc?

    in C++ I can use:
    PHP Code:
    someStruct *pSs = new someStruct
    But in C, which:
    PHP Code:
    someStruct *pSs = (someStruct*)malloc(sizeof(someStruct)); 
    or
    PHP Code:
    someStruct *pSs = (someStruct*)calloc(0sizeof(someStruct)); 
    I'm confused because I see people using both :\
    Last edited by Joelito; 03-27-2007 at 06:46 PM.
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  2. #2
    ATH0 quzah's Avatar
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    Either one works. They both do the same thing in that they allocate a block of memory. The difference is that calloc sets the values to zero, and malloc does not. You will still likely have to go and initialize your pointers manually even if you use calloc however, because a zero value does not necessarily mean NULL.


    Quzah.
    Hope is the first step on the road to disappointment.

  3. #3
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    You don't have to cast malloc(), calloc(), or realloc() in C:

    http://faq.cprogramming.com/cgi-bin/...&id=1043284351

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