topic Re: Help in automatically removing lines. in Operating System - HP-UX

Help in automatically removing lines.

Soul_1 — Mon, 01 Mar 2010 11:24:33 GMT

Hi,

i just want to remove the lines in a file from a particular text to end of the file.

eg: consider a file "test" in that
line no 1
line no 2
line no 3
#new lines
Word1
word2

my requirement is to remove the lines after "#new lines"

Please suggest me on the same.

Re: Help in automatically removing lines.

Soul_1 — Mon, 01 Mar 2010 11:26:26 GMT

hi

Forget to mention :

I need one script to automatically read and delete the kines after the particular text.

Regards,

Re: Help in automatically removing lines.

Dennis Handly — Mon, 01 Mar 2010 11:45:49 GMT

awk '
/#new lines/ {
print $0
exit
}
{print $0}' file > file.new

Re: Help in automatically removing lines.

Soul_1 — Mon, 01 Mar 2010 12:13:58 GMT

Hi Dennis,

Thanks for your response.
Can you brief what this script will do ?

Re: Help in automatically removing lines.

Dennis Handly — Mon, 01 Mar 2010 12:16:39 GMT

>Can you brief what this script will do?

It will print lines from file to file.new.
When it sees a line with "#new lines", it will print that, then exit.

Re: Help in automatically removing lines.

James R. Ferguson — Mon, 01 Mar 2010 12:50:12 GMT

Hi:

One way is:

# sed -n '1,/^#new/p' file

This begins by turning off any printing (the '-n'). If the line number is within the inclusive range of line number one (1) through a line that begins (^) with the string "new", then print the line.

Regards!

...JRF...

Re: Help in automatically removing lines.

Hemmetter — Mon, 01 Mar 2010 13:05:53 GMT

Hi
and inversed expression to JRF's sed:

# sed '/new lines/,$d' test

rgds
HGH

Re: Help in automatically removing lines.

Arturo Galbiati — Tue, 02 Mar 2010 08:40:31 GMT

hello,
in general to delete lines between START END:
sed -n'/^START/,/^END/d' file.in >file.out

HTH,
Art

Re: Help in automatically removing lines.

Steve Post — Tue, 02 Mar 2010 13:02:25 GMT

Don't forget about that -n in the sed command. It tells sed to suppress printing out unless you call for it.

$ cat junk
one
two
three
START
four
five
six
seven
END
eight
nine
ten

$ cat junk | sed '/^START/,/^END/d'
one
two
three
eight
nine
ten

$ cat junk | sed -n '/^START/,/^END/p'
START
four
five
six
seven
END

Re: Help in automatically removing lines.

Siddhartha Sarkar — Tue, 02 Mar 2010 14:16:43 GMT

you can use :
echo "head -$(($(grep -n '#new lines' test | awk -F : '{print ($1)}') -1 )) test >> test2" |sh

This will find the line number where pattern #new lines is , then subtract 1 from it and use head to put it in another file test2.

Thanks

Re: Help in automatically removing lines.

Dennis Handly — Wed, 03 Mar 2010 09:58:09 GMT

>Siddhartha: This will find the line number where pattern #new lines is

And will also read the whole file, then the first part again.

Re: Help in automatically removing lines.

Soul_1 — Mon, 08 Mar 2010 08:43:26 GMT

Hi,

I want to print the previous day date.
Please let me know how can i achieve it.

Thanks in advance

Re: Help in automatically removing lines.

Horia Chirculescu — Mon, 08 Mar 2010 08:49:46 GMT

Hello,

echo `(export TZ=XYZ+24; date "+%d/%m/%y")`

Horia.

Re: Help in automatically removing lines.

Soul_1 — Mon, 08 Mar 2010 08:58:45 GMT

Hi Horia,

Thanks a lot for your response

can you just brief what this command will do ?

Also what will happen at the starting of month. say jan 1. In that case will it display the last year an last month date ?

Regards,

Re: Help in automatically removing lines.

Horia Chirculescu — Mon, 08 Mar 2010 09:01:42 GMT

Hello.

>Also what will happen at the starting of month. say jan 1. In that case will it display the last year an last month date ?

Yes, it will work. Will work also on March, 1 showing February 28/29 and so...

Horia.

Re: Help in automatically removing lines.

Soul_1 — Mon, 08 Mar 2010 09:08:36 GMT

Hi,
I want to customize the year part of the o/p.

rt now its showing as 07/03/10 , iwant it in 07/03/2010.

Regards

Re: Help in automatically removing lines.

Horia Chirculescu — Mon, 08 Mar 2010 10:09:55 GMT

>now its showing as 07/03/10 , iwant it in 07/03/2010.

Just change %y with %Y

man date should help.

Horia.

Re: Help in automatically removing lines.

James R. Ferguson — Mon, 08 Mar 2010 12:46:06 GMT

Hi:

> I want to customize the year part of the o/p...its showing as 07/03/10 , i want it in 07/03/2010

# perl -MPOSIX -le 'print strftime "%02m/%02d/%Y",localtime(time-(60*60*24))'

...will give you yesterday's date correctly, crossing year boundaries as necessary.

You can change the format of the output just like you would using a simple 'date' command format.

Do *not* be fooled by trying to manipulate your 'TZ' variable by adding or subtracting 24-hours. This works correctly only for UTC (GMT) timezones. Use Perl;

Regards!

...JRF...

Re: Help in automatically removing lines.

Horia Chirculescu — Tue, 09 Mar 2010 06:21:29 GMT

James: > This works correctly only for UTC (GMT) timezones

Can you please explain this?

Horia.

Re: Help in automatically removing lines.

Dennis Handly — Tue, 09 Mar 2010 09:18:28 GMT

>Horia: Can you please explain this?

The code in libc only expects to have valid timezones. These are UTC +/- 12 hours.

What you did was:
$ TZ=XYZ+24 date "+%d/%m/%y %Z"
08/03/10 XYZ

This converts to UTC time and adds 24 hours. What if there was a DST transition and you skip or lose a day?