It depends on whether you partition correctly. Let's for example say you have these 2 partitions:
Code:
sda1 - Recovery
sda2 - Windooze C:
Typically, Win will use the remainder of the disk for its partition(s), which means there is no free space for your Slackware partition(s). This means that you need to re-size the sda2 partition, and resizing partitions require something else than cfdisk feat on the Slackware CD. Here's what I would do:
First, make a live CD of
Gparted Live. This is a partition-centric distro.
Boot the live CD, then make a backup of your partition table and Recovery partition;
Code:
$ fdisk -l > partitions.txt
will create a text file with the partition table. Save this on a USB disk/thumb drive for safekeeping.
Code:
$ dd if=/dev/sda1 of=recovery_part.img
will create a backup image of your partition. Save this to a USB disk/thumb drive for safekeeping.
If you want to be completely safe, skip the 2 steps above and do a full backup of the entire disk (minus free space) using a tool like clonezilla to a USB disk or something. If anything goes wrong, you can restore from that backup.
Now open the Gparted tool from Gparted Live's desktop. Resize the Windooze partition(s) so that you have sufficient free space to install Slackware and save your slackware files on (full slackware install is 5GB+ and you must also have room for _your_ files).
In the free space (say it's 20GB), create a ~7GB+ partition for /, a SWAP partition 2x the size of your physical RAM, and the rest for a /home partition. Now you have:
Code:
sda1 Recovery
sda2 Windooze
sda3 Slackware root /
sda4 EXTENDED
sdb1 SWAP
sdb2 /home
Primary partitions are limited to 4 entries AFAIK, so you'll need to make the 4th an extended partition. Execute the changes so a new partition table is written, then right-click the / and /home partitions and format to ext4 (or whatever you prefer). Mark the SWAP as swap. Execute the changes and reboot.
Put your Slackware install CD into the drive and boot it. Run mkswap /dev/sdb1 to activate the swapspace. Type setup to start the setup.
Select /dev/sda3 as TARGET, and add /dev/sdb2 as /home. Then go through the rest of the install steps.
Write lilo.conf (bootloader) to MBR, reboot when done. Now you need to add Windows and recovery partition to the /etc/lilo.conf list.
Here's an example with both Slackware and Windooze, notice the boot= option which tells the machine what the default will be.
I know it is possible to edit the boot menu in windooze as well, but I'm not too familiar with it. Lilo works. For a full list of features, see:
http://linux.die.net/man/5/lilo.conf