In Linux various special files can be found under the directory /dev. These files are called device files and behave unlike ordinary files. The most common types of device files are for block devices and character devices. These files are an interface to the actual driver (part of the Linux kernel) which in turn accesses the hardware. Another, less common, type of device file is the named pipe. The most important device files are listed in the tables below. fd0 First Floppy Drive fd1 Second Floppy Drive hda IDE Hard disk / CD-ROM on the first IDE port (Master) hdb IDE Hard disk / CD-ROM on the first IDE port (Slave) hdc IDE Hard disk / CD-ROM on the second IDE port (Master) hdd IDE Hard disk / CD-ROM on the second IDE port (Slave) hda1 First partition of the first IDE hard disk hdd15 Fifteenth partition of the fourth IDE hard disk sda SCSI Hard disk with lowest SCSI ID (e.g. 0) sdb SCSI Hard disk with next higher SCSI ID (e.g. 1) sdc SCSI Hard disk with next higher SCSI ID (e.g. 2) sda1 First partition of the first SCSI hard disk sdd10 Tenth partition of the fourth SCSI hard disk sr0 SCSI CD-ROM with the lowest SCSI ID sr1 SCSI CD-ROM with the next higher SCSI ID ttyS0 Serial port 0, COM1 under MS-DOS ttyS1 Serial port 1, COM2 under MS-DOS psaux PS/2 mouse device gpmdata Pseudo device, repeater data from GPM (mouse) daemon cdrom Symbolic link to the CD-ROM drive mouse Symbolic link to the mouse device file null Anything written to this device will disappear zero One can endlessly read zeros out of this device The mouse can be used in both the Linux console (with gpm) and the X window environment. The two uses can be made compatible if the gpm repeater is used to allow the signal to flow to the X server as shown: mouse => /dev/psaux => gpm => /dev/gpmdata -> /dev/mouse => X /dev/ttyS0 (repeater) (symlink) /dev/ttyS1 Set the repeater protocol to be raw (in /etc/gpm.conf) while setting X to the original mouse protocol in /etc/X11/XF86Config or /etc/X11/XF86Config-4. This approach to use gpm even in X has advantages when the mouse is unplugged inadvertently. Simply restarting gpm with # /etc/init.d/gpm restart will re-connect the mouse in software without restarting X. If gpm is disabled or not installed for some reason, make sure to set X to read directly from a mouse device such as /dev/psaux. For details, refer to the 3-Button Mouse mini-Howto at /usr/share/doc/HOWTO/en-txt/mini/3-Button-Mouse.gz, man gpm, /usr/share/doc/gpm/FAQ.gz, and README.mouse. For PowerPC, in /etc/X11/XF86Config or /etc/X11/XF86Config-4, set the mouse device to "/dev/input/mice". Modern kernels give you the capability to emulate a three-button mouse when your mouse only has one button. Just add the following lines to /etc/sysctl.conf file. # 3-button mouse emulation # turn on emulation /dev/mac_hid/mouse_button_emulation = 1 # Send middle mouse button signal with the F11 key /dev/mac_hid/mouse_button2_keycode = 87 # Send right mouse button signal with the F12 key /dev/mac_hid/mouse_button3_keycode = 88 # For different keys, use showkey to tell you what the code is. A standard installation for the i386 architecture, including all standard packages and using the default 2.6 kernel, takes up 442MB of disk space. A minimal base installation, without the Standard system task selected, will take 230MB. In both cases this is the actual disk space used after the installation is finished and any temporary files deleted. It also does not take into account overhead used by the file system, for example for journal files. This means that significantly more disk space is needed both during the installation and for normal system use. The following table lists sizes reported by aptitude for the tasks listed in tasksel. Note that some tasks have overlapping constituents, so the total installed size for two tasks together may be less than the total obtained by adding up the numbers. Note that you will need to add the sizes listed in the table to the size of the standard installation when determining the size of partitions. Most of the size listed as Installed size will end up in /usr and in /lib; the size listed as Download size is (temporarily) required in /var. Task Installed size (MB) Download size (MB) Space needed to install (MB) Desktop environment 1267 420 1667 Laptop There is a large overlap of the Laptop task with the Destop environment task. If you install both, the Laptop task will only require a few MB additional disk space. 50 17 67 Web server 35 11 46 Print server 277 79 356 DNS server 2 1 3 File server 49 21 70 Mail server 13 5 18 SQL database 24 8 32 The Desktop task will install the GNOME desktop environment. If you install in a language other than English, tasksel may automatically install a localization task, if one is available for your language. Space requirements differ per language; you should allow up to 350MB in total for download and installation.