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POC pointers inconsistency
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copied!<p>I'm working on a program for a C class and I reached a point where I don't know what to do. We are implementing a String library type.</p> <p>I have my header file (MyString.h)</p> <pre><code>typedef struct { char *buffer; int length; int maxLength; } String; String *newString(const char *str); </code></pre> <p>The file implementing the functions (MyString.c)</p> <pre><code>#include <stdlib.h> #include <stdio.h> #include "MyString.h" String *newString(const char *str) { // Allocate memory for the String String *newStr = (String*)malloc(sizeof(String)); if (newStr == NULL) { printf("ERROR: Out of memory\n"); return NULL; } // Count the number of characters int count; for (count = 0; *(str + count) != '\0'; count++); count++; // Allocate memory for the buffer newStr->buffer = (char*)malloc(count * sizeof(char)); if (newStr->buffer == NULL) { printf("ERROR: Out of memory\n"); return NULL; } // Copy into the buffer while (*str != '\0') *(newStr->buffer++) = *(str++); *(++newStr->buffer) = '\0'; // Set the length and maximum length newStr->length = count; newStr->maxLength = count; printf("newStr->buffer: %p\n",newStr->buffer); // For testing purposes return newStr; } </code></pre> <p>And a tester (main.c)</p> <pre><code>#include <stdio.h> #include "MyString.h" main() { char str[] = "Test character array"; String *testString = newString(str); printf("testString->buffer: %p\n",testString->buffer); // Testing only } </code></pre> <p>The problem is that, even though testString is pointing to the String created in newString(), their buffers point to different memory addresses. Why is that?</p> <p>Thanks in advance</p>

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