fusl/src/stdio/tmpnam.c

#include <stdio.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/stat.h>
#include <string.h>
#include "syscall.h"

#define MAXTRIES 100

char* __randname(char*);

char* tmpnam(char* buf) {
  static char internal[L_tmpnam];
  char s[] = "/tmp/tmpnam_XXXXXX";
  int try
    ;
  int r;
  for (try = 0; try < MAXTRIES; try ++) {
    __randname(s + 12);
#ifdef SYS_lstat
    r = __syscall(SYS_lstat, s, &(struct stat){0});
#else
    r = __syscall(SYS_fstatat, AT_FDCWD, s, &(struct stat){0},
                  AT_SYMLINK_NOFOLLOW);
#endif
    if (r == -ENOENT)
      return strcpy(buf ? buf : internal, s);
  }
  return 0;
}