2. Compiling and installing dosemu

2.1 Where are the installation instructions?

The installation instructions are in the file, "QuickStart", included in the distribution.

2.2 Top ten problems while compiling and installing dosemu.

1. Forgetting to read the QuickStart Guide.

2. Try to compile some old version of dosemu.

3. Try to compile with a kernel older than 2.0.28 or 2.1.15.

4. Having the wrong linux kernel source sitting in /usr/src/linux or missing /usr/src/linux/include/version.h

5. Use dosemu with a kernel that does not have IPC compiled in.

6. Compile with gcc older than 2.7.2 or libc older than x.x.x.

7. Forget to edit your /etc/dosemu.conf file.

8. Forget to run "FDISK /mbr" on your hdimage.

9. Run DOSEMU with partition access while they are already mounted.

10. Don't install dosemu with sufficient privileges (i.e., root). (97/2/11)

2.3 How can I use dosemu on an older version of the Linux Kernel.

If you still use 1.2.13 and can't upgarde for some reasons, use dosemu-0.60.4. If you use some version of dosemu below 2.0.28 and 2.1.15, Hans Lermen ( lermen@elserv.ffm.fgan.de) reported (97/1/25 and 97/2/11)

> Is the dosemu-0.64.3.tgz version of dosemulator for the 2.xx.yy versions > of the linux kernel ??

Yes, but ...

  if ( ((xx == 0) && (yy >= 28)) || ((xx >= 1) && (yy >= 15)) )
    take_dosemu_0_64_4();
  else {
    if (xx == 1)  exit(1);
    take_dosemu_0_64_2_x();
  }

;-)

2.4 How do I make aout binaries?

Starting with version 0.64.4 there is no a.out support any more. If you absolutely need it, you must use version 0.64.3.1. The configure script then should take care for this, if you setup is a standard setup(97/2/11).

2.5 How do I compile dosemu on a machine with low memory?

Marty Leisner (leisner@sdsp.mc.xerox.com) reported (95/4/8) that

If you have problems with running out of swap space you may want to add CFLAGS+=-fno-inline after CFLAGS is defined in dpmi/Makefile. Be careful before you do this and check for the existence of swap space. I found Linux crashes a times when it has no swap space.

2.6 Compilation fails with some strange error regarding "slang"

You probably have installed your own version of the Slang library. Hans Lermen <lermen@elserv.ffm.fgan.de> writes(97/2/11):

  configure --enable-force-slang

2.7 What configurabe options are available

Try

configure --help

2.8 How can I speed up compilation?

Marty Leisner (leisner@sdsp.mc.xerox.com) reported (95/4/8) that

The default optimization is -O2. You may want edit the makefile to use -O (compiled somewhat faster/smaller).

2.9 More compilation tips from Marty...

Marty Leisner (leisner@sdsp.mc.xerox.com) reported (95/4/8) that

You need to have build the kernel on your system to get the current version. If not, you may want to hand modify KERNEL_VERSION in the top level Makefile. The number is of the form, "nmmmppp", where "n" is the version, "mmm" is the minor version, and "ppp" is the patchlevel. For example, kernel 1.1.88 corresponds to "1001088" and kernel 1.2.1 to "1002001".

Addition from (lermen@elserv.ffm.fgan.de):

For versions greater 0.64.3 this no longer is true. You need to have a valid <linux/version.h>, which has to be part off your standard /usr/include. If you don't have it, you either did a 'make clean' on your kernel source or your distributor failed to support you with this.

2.10 Do I need to compile dosemu as root?

(95/4/8)

No. You must install it as root, though.

Marty Leisner (leisner@sdsp.mc.xerox.com) adds

In order to access I/O ports (including the console) dosemu needs to run as root. Running dosemu on an xterm or in X windows and requiring now direct hardware access allows you to run dosemu as a user. The security/setuid implications will be worked on in development releases(95/8/11).

Have a look at ..;/doc/SECURITY.readme too(97/2/9).

2.11 How to I patch dosemu.

If you do patch dosemu from one version to another, do "make pristine;./configure; make". If you don't make pristine, at least the version of the new executable will be wrong, if the whole thing compiles at all(97/2/9).

2.12 What versions of DOS are known to run with dosemu.

Caldera's OpenDos (formerly known as DrDOS) is reported to work with dosemu (Nicolas St-Pierre <draggy@kosmic.org>. As OpenDos can be used free of charge for non-commercial use, it is preferred. However as of now, redistribution is not allowed. You must get OpenDos youself from Caldera's site http://www.caldera.com/dos Hopefully this will change soon, so dosemu can distribute a bootable hdimage. MsDos-6.22 is known to work with dosemu. MsDos-7 aka Win95 works with dosemu to, supposed you have the boot logo switched off and you don't start the graphic shell at bootup. If you make the hdimage bootable with the so called "Rescue Disk" you are offered to make during the Windows installation, you get the right settings. If you use your normal Win95 installation to transfer the system files, have a look at the msdos.sys written on the hdimage and change the settings under the section Options to have entries like Options Logo=0 BootGUI=0

(97/3/7)