return of malloc() function
malloc() function is said to return a null pointer or a pointer to the allocated space. Suppose for a string we make the statement:
char* ptr = malloc(size)
Isn't ptr a pointer that would point to a pointer?
Isn't :
char** ptr = malloc(size)
supposed to be the correct way to declare the pointer to char?
The compiler however doesn't give a warning when we do either, the warning it does give is for the format specifier if used.
How should we declare this and why? Also, how would char** be used?
The char * denotes a char pointer. Malloc will return a void * pointer (that will be automatically converted to whatever pointer you're trying to assign).
The char ** denotes a char * pointer. This is a pointer to a pointer.
If you think of a pointer as a map you have that char * is a map to a char, void * is a map to something mysterious and char ** is a map to another map that leads to a char. So
char* ptr = malloc(size);
Is the correct one, because you want a map to something, not a map to a map.
No, 'ptr' would contain the pointer returned by 'malloc'. You are assigning the returned pointer, not taking its address.
*ptr is a pointer to a char, which is often used to manage an array or a string.
**ptr is a pointer to a pointer to a char, which is often used to
manage a matrix (array of arrays) or a string array.
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