1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
|
#define _GNU_SOURCE /* See feature_test_macros(7) */
#include <unistd.h>
#include <stdlib.h>
#include <assert.h>
#include <stdio.h>
#define assert_success(e) do { if ((e) < 0) { perror(#e); abort(); } } while (0)
void set_env_prefix(char *env, char *sep, char *prefix) {
char *existing = getenv(env);
if (existing) {
char *val;
assert_success(asprintf(&val, "%s%s%s", prefix, sep, existing));
assert_success(setenv(env, val, 1));
free(val);
} else {
assert_success(setenv(env, prefix, 1));
}
}
int main(int argc, char **argv) {
set_env_prefix("PATH", ":", "/usr/bin/");
set_env_prefix("PATH", ":", "/usr/local/bin/");
argv[0] = "/send/me/flags";
return execv("/send/me/flags", argv);
}
|