delete first 100 lines rather than zero out of file Post: 302145490

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Operating Systems Solaris delete first 100 lines rather than zero out of file Post 302145490 by thepurple on Wednesday 14th of November 2007 11:37:56 AM

11-14-2007

Registered User

delete first 100 lines rather than zero out of file

Hi all, i told you i m getting mainly prob with frequently growing 2 files /var/adm/messages OR /var/adm/wtmpx.
I got a solution for overgrowing wtmpx. Below is the line need to put in cronjob. it will empty wtmpx file after every 30 minutes.

30 * * * * su - root -c "cat /dev/null > /var/adm/wtmpx" > /dev/null 2>&1

I get it from sun solaris 8. Although i am using solaris 9 but hope line should work it also . However, can anyone tell me what is the value here "root -c" and "2>&1"??

Quote:

Originally Posted by thepurple

Hi soliberus,
I tried to delete first 100 lines of file messages with command # sed '1,100d' messages. But it is not working. Please see below.
bash-2.05# cat messages |wc -l
36948
bash-2.05# sed '1,100d' messages
bash-2.05# cat messages |wc -l
36949
bash-2.05#

And about 'wtmpx'- the file is not understanble to me Smilie

. So, i plan to delete only lines from 'messages'
bash-2.05# tail -f wtmpx
bgwftpftp10010'G4)192.168.210.35bgwftpftp10010G4)192.168.210.35bgwftpftp10012'G4)192.168.210.35bgwft pftp10011'4)192.168.210.42bgwftpftp10012G4)192.168.210.35bgwftpftp100114)192.168.210.42bgwftpftp1001 3'G4*192.168.210.35bgwftpftp10013G4*192.168.210.35bgwftpftp10014'G4+192.168.210.42bgwftpftp10014G4+1 92.168.210.42bgwftpftp10015'G4+192.168.210.37bgwftpftp10015G4+192.168.210.37bgwftpftp10016' G4+192.168.210.40bgwftpftp10016'G4+192.168.210.40bgwftpftp10017'!G4+192.168.210
bash-2.05# cat wtmpx |wc -l
13
Though it shows only 13 lines and lines are growing slowly but File size is growing to much fast.

thepurple

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LEARN ABOUT DEBIAN

prips

PRIPS(1)						    BSD General Commands Manual 						  PRIPS(1)

NAME

     prips -- print the IP addresses in a given range

SYNOPSIS

     prips [-c] [-d delim] [-e exclude] [-f format] [-i incr] start end
     prips [-c] [-d delim] [-e exclude] [-f format] [-i incr] CIDR-block
     prips -h

DESCRIPTION

     The prips tool can be used to print all of the IP addresses in a given range.  It can enhance tools that only work on one host at a time,
     e.g.  whois(1).

     The prips tool accepts the following command-line options:

     -c      Print the range in CIDR notation.

     -d delim
	     Set the delimiter to the character with ASCII code delim where 0 <= delim <= 255.

     -e <x.x.x,x.x>
	     Exclude ranges from the output.

     -f format
	     Set the format of addresses (hex, dec, or dot).

     -h      Show summary of options.

     -i incr
	     Set the increment to 'x'.

ENVIRONMENT

     The prips tool's operation is not influenced by any environment variables.

FILES

     The prips tool's operation is not influenced by any files.

EXAMPLES

     Display all the addresses in a reserved subnet:

	   prips 192.168.32.0 192.168.32.255

     The same, using CIDR notation:

	   prips 192.168.32/24

     Display only the usable addresses in a class A reserved subnet using a space instead of a newline for a delimiter:

	   prips -d 32 10.0.0.1 10.255.255.255

     Display every fourth address in a weird block:

	   prips -i 4 192.168.32.7 192.168.33.5

     Determine the smallest CIDR block containing two addresses:

	   prips -c 192.168.32.5 192.168.32.11

DIAGNOSTICS

     The prips utility exits 0 on success, and >0 if an error occurs.

SEE ALSO

     ipsc(1), gipsc(1)

STANDARDS

     No standards were harmed in the writing of the prips tool.

HISTORY

     The prips tool was originally written by Daniel Kelly and later adopted by Peter Pentchev.  This manual page was originally written by Juan
     Alvarez for the Debian GNU/Linux system and later added to the prips distribution and converted to mdoc format by Peter Pentchev.

AUTHORS

     Daniel Kelly <dan@vertekcorp.com>
     Juan Alvarez <jalvarez@fluidsignal.com>
     Peter Pentchev <roam@ringlet.net>

BUGS

     Please report any bugs in the prips tool to its current maintainer, Peter Pentchev.

BSD
								   March 1, 2011							       BSD

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