Questions in: Unix

Yes..:)
just open unix prompt
vi " " or vi "ab cd"
echo "jagadeeb"
:wq
just give permission :)like
chmod 777 " " or chmod 777 "ab cd"
and run that like
./" " or ./"ab cd"
out put like
jagadeeb
jagadeeb@gmail.com

Unix-legitimate filenames are any combination of these
three classes of characters: Upper and lower case letters:
A - Z and a - z
Numbers 0 - 9
Periods, underscores, hyphens . _ -
Note that line spaces (aka "whitespace") are not allowed in
filenames. The Unix shell will think you mean more than one
file.

awk 'NR % 50 == 0' print

awk 'NR % 50 ==0 {print}' filename

Sorry Sudhir,
Your syntax is wrong.It should be
paste file1 file2|cut -d " " -f2,3,4
But this command is n't providing the correct result.
Piz try another.

paste file1 file2 | cut -f 2,3,4 -d " "

read line;
echo $line | awk '{ for ( i = NF; i > 0; i--) print $i}' |
tr "n" " "

cho "Enter Choice"
read num
case $num in
1) echo `date`
;;
2) ls
;;
3) who
;;
*) echo "Wrong option press 1 2 3 only"
;;
esac

echo "Enter the number"
read i
if [ $i -eq 1 ];then
echo `date`
elif [ $i -eq 2 ];then
ls
elif [ $i -eq 3 ];then
who
else
echo "Nothing"
fi

write code like this :
#!/bin/bash
echo "My script2 call"
/bin/bash ./script2.sh [ or /bin/ksh ./script2.sh ]
It will run ..... enjoy !!!!!!

instead of
. script2.sh
Just try
sh script2.sh
It will Run

1.Data Abstraction
2.Data Encapsulation
3.Polymorphism
4.Inheritance

$ ls -al | sort -n -k5
The -n in my example means "sort numerically", and the -k5
option means to key off of column five. Like other Unix
commands, these options can be combined and shortened, like
this:
$ ls -al | sort -nk5

ls -l|sort -nk5

echo 'obase=16 ; ibase =2 ; binaryno'|bc #print hexadecimal
echo 'obase=2 ; ibase=16; hexa no'|bc #print binary no

type "r". It will execute the last executed command

esp + p enter
upper arrow enter

follow sunitabh Das unix book

It is in /var/spool/cron/crontabs
Each user have seperate file in this location. moreover
normal user cannot view this file, only root user can
access.

Check which packages are installed. Your best bet is here:
/etc/anacrontab
/etc/cron.d
/etc/cron.daily
/etc/cron.hourly
/etc/cron.monthly
/etc/cron.weekly
/etc/crontab
/var/spool/anacron
/var/spool/cron
/var/spool/anacron/cron.daily
/var/spool/anacron/cron.monthly
/var/spool/anacron/cron.weekly

login to the remote server using ssh and use top -d1 command
, it will show the load average on the server.

cat test.txt | tr '[a-z A-Z]' '[f-za-e F-ZA-E]'

cat abc.txt | tr '[a-z A-Z]' '[f-za-e F-ZA-E]' > xyz.txt

Shell is a program that takes commands as an input from the
user and interact with the Operating system to execute
those commands.Shell is a wraper around the Operating
system and passes on the information in form of the
commands to get the task done.

echo -n "Enter numnber : "
read n
rem=$(( $n % 2 ))
if [ $rem -eq 0 ]
then
echo "$n is even number"
else
echo "$n is odd number"
fi

echo "Enter the Number"
read a
b=`echo "$a % 2"|bc`
if [ $b -eq 0 ]
then
echo "Given Number is Even "
exit
fi
echo " Given Number is odd"