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diff --git a/devdocs/c/memory%2Fcalloc.html b/devdocs/c/memory%2Fcalloc.html deleted file mode 100644 index 4c0abf87..00000000 --- a/devdocs/c/memory%2Fcalloc.html +++ /dev/null @@ -1,62 +0,0 @@ - <h1 id="firstHeading" class="firstHeading">calloc</h1> <table class="t-dcl-begin"> <tr class="t-dsc-header"> <th> Defined in header <code><stdlib.h></code> </th> <th> </th> <th> </th> </tr> <tr class="t-dcl"> <td class="t-dcl-nopad"> <pre data-language="c">void* calloc( size_t num, size_t size );</pre> -</td> <td class="t-dcl-nopad"> </td> <td class="t-dcl-nopad"> </td> </tr> </table> <p>Allocates memory for an array of <code>num</code> objects of <code>size</code> and initializes all bytes in the allocated storage to zero.</p> -<p>If allocation succeeds, returns a pointer to the lowest (first) byte in the allocated memory block that is suitably aligned for any object type with <a href="../language/object#Alignment" title="c/language/object">fundamental alignment</a>.</p> -<p>If <code>size</code> is zero, the behavior is implementation defined (null pointer may be returned, or some non-null pointer may be returned that may not be used to access storage).</p> -<table class="t-rev-begin"> <tr class="t-rev t-since-c11"> -<td> <p><code>calloc</code> is thread-safe: it behaves as though only accessing the memory locations visible through its argument, and not any static storage.</p> -<p>A previous call to <code><a href="free" title="c/memory/free">free</a></code> or <code><a href="realloc" title="c/memory/realloc">realloc</a></code> that deallocates a region of memory <i>synchronizes-with</i> a call to <code>calloc</code> that allocates the same or a part of the same region of memory. This synchronization occurs after any access to the memory by the deallocating function and before any access to the memory by <code>calloc</code>. There is a single total order of all allocation and deallocation functions operating on each particular region of memory.</p> -</td> <td><span class="t-mark-rev t-since-c11">(since C11)</span></td> -</tr> </table> <h3 id="Parameters"> Parameters</h3> <table class="t-par-begin"> <tr class="t-par"> <td> num </td> <td> - </td> <td> number of objects </td> -</tr> <tr class="t-par"> <td> size </td> <td> - </td> <td> size of each object </td> -</tr> -</table> <h3 id="Return_value"> Return value</h3> <p>On success, returns the pointer to the beginning of newly allocated memory. To avoid a memory leak, the returned pointer must be deallocated with <code><a href="free" title="c/memory/free">free()</a></code> or <code><a href="realloc" title="c/memory/realloc">realloc()</a></code>.</p> -<p>On failure, returns a null pointer.</p> -<h3 id="Notes"> Notes</h3> <p>Due to the alignment requirements, the number of allocated bytes is not necessarily equal to <code>num * size</code>.</p> -<p>Initialization to all bits zero does not guarantee that a floating-point or a pointer would be initialized to <span class="nu16">0.0</span> and the null pointer value, respectively (although that is true on all common platforms).</p> -<p>Originally (in C89), support for zero size was added to accommodate code such as</p> -<div class="c source-c"><pre data-language="c">OBJ* p = calloc(0, sizeof(OBJ)); // "zero-length" placeholder -... -while(1) -{ - p = realloc(p, c * sizeof(OBJ)); // reallocations until size settles - ... // code that may change c or break out of loop -}</pre></div> <h3 id="Example"> Example</h3> <div class="t-example"> <div class="c source-c"><pre data-language="c">#include <stdio.h> -#include <stdlib.h> - -int main(void) -{ - int* p1 = calloc(4, sizeof(int)); // allocate and zero out an array of 4 int - int* p2 = calloc(1, sizeof(int[4])); // same, naming the array type directly - int* p3 = calloc(4, sizeof *p3); // same, without repeating the type name - - if (p2) - { - for (int n = 0; n < 4; ++n) // print the array - printf("p2[%d] == %d\n", n, p2[n]); - } - - free(p1); - free(p2); - free(p3); -}</pre></div> <p>Output:</p> -<div class="text source-text"><pre data-language="c">p2[0] == 0 -p2[1] == 0 -p2[2] == 0 -p2[3] == 0</pre></div> </div> <h3 id="References"> References</h3> <ul> -<li> C23 standard (ISO/IEC 9899:2023): </li> -<ul><li> 7.22.3.2 The calloc function (p: TBD) </li></ul> -<li> C17 standard (ISO/IEC 9899:2018): </li> -<ul><li> 7.22.3.2 The calloc function (p: 253) </li></ul> -<li> C11 standard (ISO/IEC 9899:2011): </li> -<ul><li> 7.22.3.2 The calloc function (p: 348) </li></ul> -<li> C99 standard (ISO/IEC 9899:1999): </li> -<ul><li> 7.20.3.1 The calloc function (p: 313) </li></ul> -<li> C89/C90 standard (ISO/IEC 9899:1990): </li> -<ul><li> 4.10.3.1 The calloc function </li></ul> -</ul> <h3 id="See_also"> See also</h3> <table class="t-dsc-begin"> <tr class="t-dsc"> <td colspan="2"> <span><a href="https://en.cppreference.com/w/cpp/memory/c/calloc" title="cpp/memory/c/calloc">C++ documentation</a></span> for <code>calloc</code> </td> -</tr> </table> <div class="_attribution"> - <p class="_attribution-p"> - © cppreference.com<br>Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.<br> - <a href="https://en.cppreference.com/w/c/memory/calloc" class="_attribution-link">https://en.cppreference.com/w/c/memory/calloc</a> - </p> -</div> |