Shell Commands


Simple Shell commands for Informational purposes

    crontab ?l

    to list the system conjobs

    cat [opts] [filepattern] ?Print file contents on STOUT
    -E :Display a $ at the end of each line.
    -T :Show tabs as ^I.
    -v :Show non-printing characters.

    date [opts] ?Print or set the system date and time
    –date=STRING :display time described by STRING.
    –set=STRING :set time described by STRING.

    dmesg [opts] ?Print or control the kernel ring buffer
    -c :Clear the contents of the ring buffer.

    file [opts] [filepattern] ?Determine the file type
    -z :Try to look inside compressed files.

    finger [opts] [userpattern] ?Show info about system users
    -m :Match the exact username specified.

    free [opts] ?Display free and used memory in the system
    -b :Display the information in bytes.

    hexdump [opts] ?Show all the characters of a file
    -c :Display the input offset in hexidecimal

    last [opts] [username] ?Show last system logins for users
    -num :Show last num of sessions.
    -a :Display the hostname in the last column.
    -d :Translates IP numbers to their hostname.

    :Use file as last log.

    less [opts] [filepattern] ?View a file a page at a time
    -i :Do case insensitive searching.
    -S :Don?t wrap long lines.

    man [opts] [section] ?View online manual pages.
    -a :View all available manual pages for name.
    -k string :Search for the specified string.

    md5sum [opts] [filepattern] ?Show the uniqueness of files

    ps [opts] ?Show what processes are running on the system
    a :Select all processes on a terminal.
    u :Display user oriented format. More columns.
    x :Select processes without a controlling TTY.
    w :Show an extra line of process entry per w.
    Ex: ps auxwww =Displays all process information on system.

    quota [opts] [user] ?Display disk usage and limits
    -v :Display filesystems where no quota is set.

    time [opts] [command] ?Show resource usage for a command

    top [opts] ?Display top CPU processes every X seconds
    -d sec :Set the delay to sec seconds before refreshing.

    umask [opts] [mode] ?Set the default file permissions
    -S :Show current symbolic umask.

    uname [opts] ? Show OS and system information
    -a :Show everything

    uptime ? Show system uptime and load

    w [opts] [user] ? Show who is logged in/what they are doing
    whereis [command] ? Locate the related files for a command
    which [command] ? Show full path to the specified command
    who [opts] [args] ? Show who is logged in

    ? Check your ps output and see what it is running:

    ps axf

    Harware info stuff :

    Information regarding partitions :

    just use shell and type df which will give you the allocated space for all your partitions !

    cat /proc/cpuinfo —-List info about CPU.

    and additional info!

    /sbin/lspci —- list all PCI devices (result of probe) Also lspci -vvx and cat /proc/pci

    cat /proc/interrupts —-List IRQ’s used by system.

    cat /proc/ioports —-List I/O ports used by system.

    cat /proc/dma —-List DMA channels and device used by system.