Adviser to Unix Commands Assorted

 25 August 20:25   

    sync address anamnesis buffers to disk

    Example:

    Sync has no options, doesnt affectation any messages

     $ accompany

    Tips:

    It is consistently acceptable to blazon accompany a brace of times, one the important action of accompany is to amend your superblock information.

    The accompany calls accompany Unix arrangement alarm and exits with success cipher 0 or 1 if it fails. These avenue codes stored in $? variable.

     $ sync

     $ answer $?

     0

    The aloft archetype shows that accompany was successful.

    echo outputs its ambit to the accepted output.

    Examples:

     $ answer accost world

     accost world

    Tips:

    Some accepted answer usage:

    Check a carapace variable:

     $ answer $EDITOR

     emacs

    Check the ambit anesthetized in the antecedent command:

     $ ls -l

     .........

     $ answer $_

     -l

    Check the accepted ancestor process:

     $ answer $0

     bash

    Check the avenue cipher of the endure command:

     $ answer $?

     0

    Create a abandoned book (same as touch /tmp/newfile):

     $ answer > /tmp/newfile

    Create a new book with some text:

     $ answer exec fluxbox > ~/.xinitrc

    Add (append) a new band to end of file:

     $ answer A New Band >> /tmp/newfile

    cal displays a calender for the accepted month. If the command is followed by a date (a ages or a year) it will acknowledgment a calender for that period.

    Examples:

     $ cal

     April 2004

     Su Mo Tu We Th Fr Sa

     1 2 3

     4 5 6 7 8 9 10

     11 12 13 14 15 16 17

     18 19 20 21 22 23 24

     25 26 27 28 29 30

     $ cal 01 2007

     January 2007

     Su Mo Tu We Th Fr Sa

     1 2 3 4 5 6

     7 8 9 10 11 12 13

     14 15 16 17 18 19 20

     21 22 23 24 25 26 27

     28 29 30 31

    Tips:

    The was adopted in the in 1752. The 2nd day of September 1752 was anon followed by the 14th day of September, as apparent by the archetype below.

     $ cal 9 1752

     September 1752

     Su Mo Tu We Th Fr Sa

     1 2 14 15 16

     17 18 19 20 21 22 23

     24 25 26 27 28 29 30

    date displays the accepted date and time.

    Example:

     $ date

     Mon Jun 26 12:34:56 CDT 2006

    time time a program

    Example:

     $ time gcc apache.c

     absolute 0m1.818s

     user 0m0.770s

     sys 0m0.210s

    from affectation the names of those who beatific you mail recently

    Example:

     $ from

     From andy@box.po Sat Feb 05 08:52:37 2005

     From andy@box.po Sat Feb 05 08:53:52 2005

    Count the amount of mail in your mailbox

     $ from -c

     There are 2 letters in your admission mailbox.

    mail allows you to apprehend and address emails.

    Example:

     $ mail

     No mail for user.

     $ mail user2

     Subject: Whats up?

     Hi user2, you can annul this debris by acute d.

     Cc: user

    Tips:

    Note that you charge to columnist access then ctrl+d to confirm.

     $ mail

     Mail adaptation 8.1 6/6/93. Blazon ? for help.

     /var/spool/mail/user: 1 bulletin 1 new

     >N 1 user@unix.com Tue Jun 27 12:34 16/674 Whats up?

     &

    Tips: Columnist access to read.

    clear clears the screen.

    Example:

     $

    PS1 is an ambiance capricious which defines the carapace prompt. If not defined, the alert defaults to $

    Example:

     $ PS1=yes?

     yes? PS1=$

     $

    A added complicated example:

     $ PS1= $