Finding pointer to argv[0] so I can change it

问题

On Solaris I got a pointer to argv[0] with getexecname and then I can memcpy at that location. (per Finding current executable's path without /proc/self/exe)

I was wondering how to get a pointer to argv[0] in Linux I did readlink on /proc/self/exe but it doesn't give me a pointer to it.

THanks

回答1:

&argv[0] gets you a pointer to argv[0].

You can overwrite the characters stored in the array that argv[0] is pointing at, so long as you don't go past the existing null terminator; however it might cause UB to try and modify the pointer argv[0].

回答2:

For readlink, Bring Your Own Buffer. You allocate a buffer, pass in a pointer to it, and readlink will store the results there:

#include <unistd.h>
#include <linux/limits.h>

int main() {
  char buffer[PATH_MAX];

  int size = readlink("/proc/self/exe", buffer, sizeof(buffer));
  buffer[size] = '\0';

  // buffer is now the char* holding the filename

  printf("The executable is %s\n", buffer);
}

来源：https://stackoverflow.com/questions/29158026/finding-pointer-to-argv0-so-i-can-change-it