C: How to Detect LD_PRELOAD

As I'm writing a lib to be preloaded under something heavy, I tried to detect if LD_PRELOAD is set or not. For fun.

The easiest way to check is...get the environment variable! It is so straightforward, that I feel the urge to write it down :-)

?

1 2 3 4 5 6 7 8 9 10

#include <stdio.h> #include <stdlib.h>   int main(void) {  char *env_val = getenv("LD_PRELOAD");  if (env_val[0] != 0) // May be set but value is empty.   printf("LD_PRELOAD active: \"%s\"\n", env_val);  return 0; }

Note, this only checks the existence of the variable, not that if it is actually loaded...