Some Thing About Linux

About Linux

Linux was developed by Linux Torvalds at the University of Helsinki in Finland. He started his work in 1991. The effort expanded with volunteers contributing code and documentation over the internet. It is currently developed under the GNU public license and is freely available in source and binary form.

Some of its features include:

1. Virtual memory, allowing the system to use disk room the same as RAM memory.
2. Networking with TCP/IP and other protocols.
3. Multiple user capability.
4. Protected mode so programs or user's can't access unauthorized areas.
5. Shared libraries
6. True multitasking
7. X - A graphical user interface similar to windows, but supports remote sessions over a network.
8. Advanced server functionality
• FTP server
• Telnet server
• BOOTP server
• DHCP server
• Samba server
• DNS server
• SNMP services
• Mail services
• Network file sharing
• much, much more...
9. Support of filesystems that other operating systems use such as DOS (FAT), Windows95,98 (FAT32), Windows NT, 2000 (NTFS), Apple, minix, and others

Reasons to use:

1. Free
2. Runs on various machine architectures
3. Works well on machines that are not "modern". Recommended 8MB RAM, with 16MB swap drive space. It will run in hard drives as small as 500MB or less.
4. Linux is stable and even if a program crashes, it won't bring the OS down.
5. Source code is available. 

System Setup

Accessing Other Filesystems

For a list of programs used to work with filesystems, see the section "Making amd Managing Filesystems". To access other filesystems you must first create them or determine what is currently on your computer. This example assumes you already have filesystems on your computer such as DOS, Windows, or Other Linux partitions you want to access.

1. Use one of two methods to determine what partitions are on each drive
1. Type "fdisk /dev/hda" for drive 1, "fdisk /dev/hdb" for drive2. then type p to see a list of each partition. Type q to exit.
2. An alternate method to do this step assuming you can boot to the filesystem using LILO is:
1. Type "less /etc/lilo.conf"
2. Look for the label used by lilo to select dos, such as "dos" and use the associated device. The line on my system is "other=/dev/hda1" so I will use device "/dev/hda1". The disadvantage here is that this method will not allow determination of file systems with no operating system such as partitions that hold data.
2. Make directories for mount points for each of the other filesystems. For another Linux install such as Debian or Slackware, Type "mkdir /debian" or "mkdir /slackw" For a foreign operating system partition such as DOS or Windows98, "type "mkdir /dos" or "mkdir /win98".
3. Type "mount –t msdos /dev/hda1 /dos" where /dev/hda1 is where the dos partition is. Type "mount /dev/hda4 /win98" to mount the windows filesystem or mount "/dev/hda3 /slackw". Your filesystems may be on other partitions than those shown in examples here.
4. You can unmount when done: "umount /dev/hda1", however the exit scripts unmounts all file systems when the system is shutdown.

The following line in /etc/fstab will cause the system upon bootup to mount an msdos partition on /dev/hda1 on the directory /dos:

        /dev/hda1      /dos    vfat           defaults   0 0

This works because one of the startup script files "/etc/rc.sysinit" includes a line "mount -a -t nonfs,smbfs,ncpfs,proc". This command mounts all filesystems listed in the file "/etc/fstab". You could set the filesystem type to msdos. Read the file, /usr/src//linux/fs/filesystems.c to find a list of supported filesystems with your kernel. The file /etc/mtab and /proc/mounts each keep a record of currently mounted filesystems on your system. Read the mount man page for more information.
Another useful command is "hdparm -g /dev/hda" which is used to determine hard drive geometry (sectors, heads, cylinders).