#include <unistd.h>
#include <paths.h>
#include <alloca.h>

extern char **environ;

int __exec_shell(const char *file, char *const argv[]);
int __exec_shell(const char *file, char *const argv[]) {
  int i;
  const char** shell_argv;

  for (i = 0; argv[i]; ++i); ++i;

  shell_argv=alloca(sizeof(char*)*(i+1));
  shell_argv[0] = _PATH_BSHELL;
  shell_argv[1] = file;
  for (; i > 1; i--)
    shell_argv[i] = argv[i - 1];
  return execve(_PATH_BSHELL, (char*const*)shell_argv, environ);
}