Frequently Asked Questions

# 4 Frequently Asked Questions

Contents of this section

This is a collection of questions I get asked once in a while, which could fall into the category of FAQ's. If you feel that there is some question that ought to be added to the list, please feel free to mail me (but do include an answer, thanks!).

## 4.1 Can I exchange tapes with someone using DOS?

No. The DOS software conforms to the QIC-80 specs about the layout of the DOS filesystem, and it should(?) be a small problem to write a program that can read/write the DOS format. In fact, I'd bet that creating a nice user interface would be a bigger problem.

## 4.2 How do I `....' with `tar`?

These are really `tar` questions: Please read the `man` page and the `info` page. If you have not got it either, try ``tar --help 2>&1 | more`'.

If your version of `tar` is v1.11.1 or earlier, consider upgrading to v1.11.2 - This version can call `GNU zip` directly (i.e.: it supports the `-z` option) and has an elaborate help included. Also, it compiles right out of the box on Linux.

## 4.3 `ftape` DMA transfers gives ECC errors

Sadly to say there are some SVGA cards and ethernet cards that do not decode their addresses correct. This typically happens when the `ftape` buffers are in the range `0x1a0000` to `0x1c0000`. Somehow, the DMA write cycles get clobbered and every other byte written gets a bad value (`0xff`). These problems are reported to happen with both SVGA and ethernet cards. We know of at least one (bad?) ATI 16bit VGA card that caused this.

The easiest solution is to put the card in an 8bit slot (it is often not enough to reconfigure the card to 8bit transfers). Moving the `ftape` buffer away from the VGA range is only a partial solution; All DMA buffers used in Linux can have this problem! Let us make this one clear: This has nothing to do with the `ftape` software.

## 4.4 `insmod` says the kernel version is wrong

The `insmod` program checks the kernel version against the version recorded in the `ftape` driver. This is a string in `kernel-version.h`, (e.g.: `char kernel_version[] = "1.1.53";`) which is extracted from the kernel you are running when you run ``make dep`'. If you got the error when you tried to insert the `ftape` driver, remove the file ``kernel-version.h`', type ``make dep ; make`' again and the `kernel-version.h` file should be updated. Remember that you will have to do this every time you change to another kernel version.

## 4.5 The `v1.1.0` kernel wont compile when `ftape` support is added

(Although I haven't heard a lot of complains, I include it here, just to be sure)

This was due to a typo (and a hacker who didn't use `ftape` himself, so he never got around to actually test the code he wrote). This is corrected by `patch1.gz`, which can be found from the usual ftp sites.

## 4.6 `ftape` complains that ```This tape has no 'Linux raw format'` ''

If you get this complain, try ``mt -f /dev/ftape erase`'. This should solve the problem.

## 4.7 Where can I find the `tar`/`mt`/`cpio`/`dd` binaries/sources/manpages?

All of these tools have been developed by the GNU project, and the source (and man page) can be fetched from just-about any ftp site in the world (including `ftp.funet.fi`, `tsx-11.mit.edu`, and `sunsite.unc.edu`). In any case they can be fetched from the official GNU home site: `prep.ai.mit.edu [18.71.0.38]:/pub/gnu`. The latest versions (by 26. march 94) are:

> `

>             cpio:   2.3 (cpio-2.3.tar.gz)
>             dd:     3.9 (fileutils-3.9.tar.gz)
>             mt:     2.3 (cpio-2.3.tar.gz)
>             tar:    1.11.2 (tar-1.11.2.tar.gz)
>             gzip:   1.2.4 (gzip-1.2.4.tar.gz)

> `

They all compile out of the box on Linux `v1.0.4` / `libc v4.5.19` / `gcc v2.5.8` (The `rmt` program does not compile out of the box, but it is not needed as it is only used for accessing the tape drive remotely).

Next Chapter, Previous Chapter

Table of contents of this chapter, General table of contents

Top of the document, Beginning of this Chapter