Question

How to initialise an element of array to NULL.For example if I have
char *array[10];
I want last element to be NULL, so that I can pass this array to execv

Answer 1

To initialise an array of char* to all NULLs:

char* array[10] = { NULL }; /* The remaining elements are implicitly NULL. */

If you want to provide initial elements for execv():

char* array[10] = { "/usr/bin/ls", "-l" }; /* Again, remaining elements NULL. */

or if you wish to omit the dimension from the array declaration:

char* array[] = { "/usr/bin/ls", "-l", NULL };