dynamic Memory allocation and free in C -

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lets have created string dynamically in program

char* s = malloc(sizeof(char) * 128);

before start using s, how check whether memory allocated or not?

free(s);

and before using free() , want check there other pointers pointing s .

malloc() returns pointer newly allocated memory or null.

so check null

char *s = malloc(128); /* sizeof (char), definition, 1 */ if (s == null) {     /* no memory allocated */ } else {     /* use memory */     free(s); }

there other pointers pointing s points if (the programmer) created them.


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