/* Test whether /proc/{self,$PID}/path/a.out is correctly simulated. */
#include <limits.h>
#include <stdio.h>
#include <strings.h>
#include <unistd.h>
#include <sys/fcntl.h>
static void test_readlink(const char *cwd, const char *label,
const char *path)
{
char buf[PATH_MAX];
int n;
if ((n = readlink(path, buf, sizeof(buf) - 1)) >= 0) {
const char *p;
size_t len = strlen(cwd);
buf[n] = '\0';
p = buf;
if (!strncmp(buf, cwd, len))
p += len;
printf("Result of readlink(\"%s\"): %s\n", label, p);
}
else
perror("readlink");
}
static void test_readlinkat(const char *cwd, const char *label,
const char *path)
{
char buf[PATH_MAX];
int n;
if ((n = readlinkat(AT_FDCWD, path, buf, sizeof(buf) - 1)) >= 0) {
const char *p;
size_t len = strlen(cwd);
buf[n] = '\0';
p = buf;
if (!strncmp(buf, cwd, len))
p += len;
printf("Result of readlinkat(\"%s\"): %s\n", label, p);
}
else
perror("readlinkat");
}
int main(void)
{
char cwd[PATH_MAX];
char path[PATH_MAX];
cwd[0] = '\0';
if (!getcwd(cwd, sizeof(cwd) - 1)) /* '-1' to make room for '/' */
perror("getcwd");
strcat(cwd, "/");
snprintf(path, sizeof(path), "/proc/%ld/path/a.out", (long)getpid());
test_readlink(cwd, "/proc/self/path/a.out", "/proc/self/path/a.out");
test_readlink(cwd, "/proc/<pid>/path/a.out", path);
test_readlinkat(cwd, "/proc/self/path/a.out", "/proc/self/path/a.out");
test_readlinkat(cwd, "/proc/<pid>/path/a.out", path);
return 0;
}