Change value in pointer string array in C -


is possible change value in character array initialized string pointer way:

char *word; word = (char*) malloc(10 * sizeof(char)); word = "test"; word[2] = 'w';  return 0;

i segmentation fault while executing above code.

you crash because this:

word = "test"; word[2] = 'w';

the first assignment changes pointer, no longer points memory have allocated string literal. , string literals read-only character arrays. , read-only, attempt of modifying array in second assignment lead undefined behavior.

the correct way copy string memory have allocated, strcpy function:

strcpy(word, "test");

another thing reassigning of pointer loose pointer allocated memory, , have memory leak. can not call free on pointer either, since memory pointed word (after original reassignment) no longer allocated you, have caused case of undefined behavior.


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