12 funny C language interview questions and answers-Comment on 12 interesting C language Q & A (4)

#include <stdio.h>

int main (void)
{
    char * ptr = "Linux";
    * ptr = 'T';

    printf ("\ n [% s] \ n", ptr);

    return 0;
}



Q: Can you write a program to change its name while it is running? (Can you write a program that changes its own name when run?)

 

#include <stdio.h>

int main (int argc, char * argv [])
{
    int i = 0;
    char buff [100];

    memset (buff, 0, sizeof (buff));

    strncpy (buff, argv [0], sizeof (buff));
    memset (argv [0], 0, strlen (buff));

    strncpy (argv [0], "NewName", 7);

    // Simulate a wait. Check the process
    // name at this point.
    for (; i <0xffffffff; i ++);

    return 0;
}
 

 int i = 0;
// ……
 for (; i <0xffffffff; i ++);

 

for (i = 0; i <0xffffffff; i ++)
   ;


    char buff [100];

    memset (buff, 0, sizeof (buff));

    strncpy (buff, argv [0], sizeof (buff));
    memset (argv [0], 0, strlen (buff));

       strncpy (argv [0], "NewName", 7);
 

Memset (buff, 0, sizeof (buff));
 

Strncpy (buff, argv [0], sizeof (buff));
 

   char s [4];
   strncpy (s, "1", 4);
   printf ("% d% d% d% d \ n", s [0], s [1], s [2], s [3]);

  49 0 0 0


memset (argv [0], 0, strlen (buff));

memset (argv [0], 0, strlen (argv [0]));

 

strncpy (argv [0], "NewName", 7);