char *error_buf;
size_t error_buf_len;
- error_buf_len = sizeof ("fopen: ") - 1 + strlen (ringfile) + 1;
+ error_buf_len = sizeof ("fopen: ") - 1 + mutt_strlen (ringfile) + 1;
error_buf = safe_malloc (error_buf_len);
snprintf (error_buf, error_buf_len, "fopen: %s", ringfile);
perror (error_buf);