Segmentation Fault in C When Accessing a Pointer in a Struct After Freeing Memory
I'm converting an old project and I'm trying to debug I'm working with a segmentation fault in my C program when I try to access a pointer inside a struct after I've freed the memory associated with that struct... The code snippet below illustrates my implementation: ```c #include <stdio.h> #include <stdlib.h> typedef struct { int value; char *text; } MyStruct; void process(MyStruct *s) { printf("Value: %d, Text: %s\n", s->value, s->text); } int main() { MyStruct *s = malloc(sizeof(MyStruct)); s->value = 42; s->text = malloc(20 * sizeof(char)); snprintf(s->text, 20, "Hello, World!"); process(s); free(s->text); free(s); // Attempting to access the struct after freeing it process(s); // This line causes a segmentation fault return 0; } ``` I've tried running the program with a debugger (gdb), and it shows that the crash occurs during the second call to `process(s);` after the memory has been freed. I understand that accessing freed memory can lead to undefined behavior, but I was hoping to understand better why this is happening in this specific case. Am I misunderstanding how memory is managed in C, or is there a better way to handle this? I've looked into using `NULL` pointers after freeing, but I'm not sure how to implement that correctly. Any suggestions or insights would be highly appreciated! My development environment is macOS. Am I missing something obvious? What are your experiences with this? This is for a web app running on Ubuntu 22.04.