Dynamically allocated string arrays in C -


i'm trying understand how dynamically allocated arrays work in c 99. anyways, have following code:

int main() {     char** members=malloc(4*sizeof(*members));     *members=malloc(5);     *members="john";     *(members+1)="shouldn't work";     printf("%s \n",*members);     printf("%s",*(members+1));     return 0; }

i thought run time error because didn't allocate (members+1), did print both "john" , "shouldn't work", also, apperas the *members=malloc(5) line wasn't necessary. why?

your assignments aren't doing think they're doing. when assign *members or *(members+1), you're assigning char* each string literal, not copying allocated (or not allocated) heap memory.

if instead replaced assignments strcpy, i.e.:

strcpy(*members, "john"); strcpy(*(members+1), "shouldn't work");

then access violation on second assignment not first. likewise, reason malloc(5) appears unnecessary because reassign pointer point string literal, instead of copying "john" string allocated memory.


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