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
27
28
29
30
31
32
33
34
35
36
37
38
|
// makeCWrapper /path/to/executable \
--prefix PATH : /usr/bin/ \
--prefix PATH : /usr/local/bin/
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <stdio.h>
#define assert_success(e) do { if ((e) < 0) { perror(#e); abort(); } } while (0)
char *concat3(char *x, char *y, char *z) {
int xn = strlen(x);
int yn = strlen(y);
int zn = strlen(z);
char *res = malloc(sizeof(*res)*(xn + yn + zn + 1));
assert(res != NULL);
strncpy(res, x, xn);
strncpy(res + xn, y, yn);
strncpy(res + xn + yn, z, zn);
res[xn + yn + zn] = '\0';
return res;
}
void set_env_prefix(char *env, char *sep, char *val) {
char *existing = getenv(env);
if (existing) val = concat3(val, sep, existing);
assert_success(setenv(env, val, 1));
if (existing) free(val);
}
int main(int argc, char **argv) {
set_env_prefix("PATH", ":", "/usr/bin/");
set_env_prefix("PATH", ":", "/usr/local/bin/");
argv[0] = "/path/to/executable";
return execv("/path/to/executable", argv);
}
|
