newbie questions about malloc and sizeof

by

sizeof(str) returns the size of a pointer of type char*. What you should do is to malloc the size of the string it self:

char * copy = malloc(strlen(str) + 1);

Also, these lines:

while(*str != '\0'){
        *copy = *str;
        str++;
        copy++;
}
copy = '\0';

Can be rewritten easily in C like this:

while(*copy++ = *str++);

More Related Contents:

  1. Getting the size of a malloc only with the returned pointer
  2. Using sizeof() on malloc’d memory [duplicate]
  3. Why do I get a warning every time I use malloc?
  4. Logic behind sizeof operator [duplicate]
  5. How to find the ‘sizeof’ (a pointer pointing to an array)?
  6. Are there machines, where sizeof(char) != 1, or at least CHAR_BIT > 8?
  7. Dynamic memory access only works inside function
  8. How can I allocate memory and return it (via a pointer-parameter) to the calling function?
  9. sprintf() with automatic memory allocation?
  10. What’s the difference between a VLA and dynamic memory allocation via malloc?
  11. How to dynamically allocate memory space for a string and get that string from user?
  12. How is malloc() implemented internally? [duplicate]
  13. Checking the size of an object in Objective-C
  14. Should I free memory before exit?
  15. What is guaranteed about the size of a function pointer?
  16. Freaky way of allocating two-dimensional array?
  17. Function to dynamically allocate matrix
  18. Include source code of malloc.c in gdb?
  19. Behavior of sizeof on variable length arrays (C only)
  20. Can I rely on malloc returning NULL?
  21. C – Accessing data AFTER memory has been free()ed?
  22. How can I find the number of elements in an array?
  23. allocate matrix in C
  24. Sizeof arrays and pointers
  25. How to find the size of an array (from a pointer pointing to the first element array)?
  26. Access struct members as if they are a single array?
  27. Problem usage memory in C
  28. realloc(): invalid next size when reallocating to make space for strcat on char * [duplicate]
  29. why sizeof(‘a’) is 4 in C? [duplicate]
  30. Minimizing the amount of malloc() calls improves performance?

Leave a Comment