[jacy]

Hi,
I need to output the long listing of files that were last modified in the month of february using the sed command from share directory. I can use other commands by piping it into sed. The problems is there were no files that were modified in february, so i have to display a message that there were no files that were modified in february. Am not familiar with the sed command. Please help. This is what i know

ls -l /share

this displays the list of all files and directories in share. I don't know how to perform an operation that checks if there were any files modified in the month of february and display a message.

[tsunam]

you could actually do this a couple of ways. basically you need a if statement of the nature:

output=`ls -l /share | (find grep sed) (date area)`
if $output == (nothing)
then
echo "no files modified"
else
echo $output
fi

something of that nature...now this by no means is a working example but it gives you a idea of where to start and go. Squash and myself will help as you figure things out and get confused but we both like to see people learn and keep that knoledge for when they need it later (in linux you'd be surprised how often some bash/sed/grep/find/etc knowledge is helpful)

[Squashman]

I don't think you will need SED to accomplish this task. As much as I love SED, I find it a challenge to find ways not to use SED. Makes things more interesting. Before we get started, could you tell me what Operating system you are running and what shell you are using.

[jacy]

Thanks for ur help am in C shell working on Red hat linux. I used awk and it works. This is what i did
ls -l /share|awk '$6!= Feb {print "No files were modified in February"}

where 6 is the the sixth field which contains the month.

But the assignment calls for sed. This is what i did with sed.
ls -l| grep Feb|sed 's/Feb/February/'|wc -l

If there is Feb the it will be replaced by February and then that will be the input for wc -l which will count the number of lines for february if any. If i can store that number in a variable then i can use that in the awk statement which will accomplish the task. How can i declare a variable. Thanks for ur time.

[Squashman]

Still not sure why you need to use sed. Why does the instructor want you to use SED. What do you mean by how do you declare a variable.

number=`ls -l| grep Feb|sed 's/Feb/February/'|wc -l`
echo $number

Is that what you want.

[tsunam]

probably to get people to understand the usefulness of sed. Professors do strang things like that :P

[Squashman]

Originally Posted by tsunam

probably to get people to understand the usefulness of sed. Professors do strang things like that :P

Yeah, I suppose. Everyone should know SED. But hey, lets make it a little more challenging then that.

[tsunam]

LOL yes let's make them learn sed + regular expressions. Oh oh and toss escape characters on top.

[jacy]

Originally Posted by Squashman

Still not sure why you need to use sed. Why does the instructor want you to use SED. What do you mean by how do you declare a variable.

number=`ls -l| grep Feb|sed 's/Feb/February/'|wc -l`
echo $number

Is that what you want.

My instructor wants us to use sed. We can use sed with other commands, but we have to use sed no matter what.

number=`ls -l| grep Feb|sed 's/Feb/February/'|wc -l`
here number is variable where the value will be stored, so i was asking how could i declare it b4 using it.

I tried the above command, it's giving me an error command not found.
Thanks for ur help.

[Squashman]

I guess I don't understand what you mean by declare. Do you mean declare whay type of variable it is like you would in a programming language.

[Squashman]

Originally Posted by jacy

I tried the above command, it's giving me an error command not found.
Thanks for ur help.

works fine on my box but I am using bash as my shell. Not sure if that makes a difference or not.

[jacy]

Originally Posted by Squashman

I guess I don't understand what you mean by declare. Do you mean declare whay type of variable it is like you would in a programming language.

Exactly, that's what i meant. I looked in the share directory, there were no files modified in February, so the line count will be always zero. I came up with this

ls -l /home/faculty/share | sed '/Feb/p' | awk '$6!=0 {print "No files were modified in February"}'| uniq

This works for me.I have used sed, and am displaying the message, since there were no files modified in Feb. Thank u squashman for ur replies.

[Squashman]

Originally Posted by jacy

Exactly, that's what i meant.

You will have to look up the syntax for your Shell environment. I don't use the C shell but I know you can do it in a bash shell.
http://linuxreviews.org/beginner/abs.../en/x4854.html