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Segmentation fault in 2D array unsigned char using calloc in C

c,arrays,char,unsigned,calloc
I've trying to allocate an unsigned char** using calloc: newmatriz = (unsigned char**) calloc(width, sizeof(unsigned char)); for (j=0 ; j < width; j++) { if (newmatriz[j]=(unsigned char*)calloc(witdh, sizeof(unsigned char)) == NULL){ printf("Memory allocation error. Exit program\n"); exit(1); } } for (i=0;i<width;i++) { for(j=0;j<width;j++) { newmatriz[i][j] = 0; } } But...

Calloc a Two-Dimensional Array

c,arrays,calloc
To make a two dimensional array, I'm currently using the following: int * own; own = (int *)calloc(mem_size, sizeof(int)); for (i=0;i<mem_size;i++){ own[i] = (int *)calloc(3, sizeof(int)); } However, every time I reference own[i][j], I get an error saying that the subscripted value is neither array nor pointer nor vector....

calloc created array is not acting as expected

c++,pointers,memory-management,calloc
I was bored and wanted to make a program to crash my computer :P. I would have it uselessly and redundantly allocate memory until the crash. The code I created so far is here: #include <cstdlib> #include <cstdio> int main(int argc, const char *argv) { int n = 0; while...

typedef pointer using fgets to input data, but takes last fgets

c,malloc,typedef,fgets,calloc
I'm trying to read postal codes from a file into an Object * array. file includes 123 Anywhere kirkland CA 99223 my .h file looks like typedef struct { char *street; char *city; char *state; int zip; }Address; my filling the array Address * fillArray(int * total, FILE * fin)...

Unable to properly free malloc of another malloc [duplicate]

c,malloc,free,dynamic-memory-allocation,calloc
This question already has an answer here: String assignment in C 4 answers Here's the snippet with issues. int main() { char** RESERV = (char**)malloc(sizeof(char*)*4); printf("%i, %i, %i, %i, %i", **RESERV, *RESERV, RESERV, &**RESERV, sizeof(char*)); int i; for(i = 0; i < 4; i++) { RESERV[i] = (char*)calloc(sizeof(char),16); RESERV[i][15]...

unexpected output while using strlen function

pointers,sizeof,calloc
#include<stdio.h> #include<stdlib.h> #include<string.h> int main() { char *p; p=calloc(10,sizeof(char)); printf("the address of pointer is %p and size of the string is %d",p,strlen(p)); return 0; } I allocated 10 bytes of memory in heap using calloc and i expect the output of size will be 10 but the output is the...

Initialize dynamically allocated structures within dynamically allocated structures

c,struct,calloc
I want to dynamically allocate structures within structures. I think I can do this. However when I want to perform operations with them, I get an access violation error under Visual C++. Perhaps there is something wrong with the initialization. By the way, how can I initialize myDynamicMembersBinArray being dynamically...