Files

32 lines
671 B
C

#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/wait.h>
#include <unistd.h>
int main(int argc, char* const* argv, const char* const* envp) {
int newfd = dup(1), outfd = dup(1);
char fd_argv[4];
snprintf(fd_argv, 4, "%d", newfd);
char* const new_argv[] = {"./exec_victim", fd_argv, NULL};
setenv("IN_EXECVE", "1", 1);
int pid = fork();
if (pid == 0) {
close(outfd);
execv(new_argv[0], new_argv);
}
wait(NULL);
FILE* out = fdopen(outfd, "a");
if (!out) {
printf("cannot open file descriptor\n");
return -1;
}
fprintf(out, "Goodbye world!\n");
return 0;
}