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Full Discussion: Delete first 100 lines from a BIG File
Top Forums UNIX for Advanced & Expert Users Delete first 100 lines from a BIG File Post 302659365 by methyl on Wednesday 20th of June 2012 07:27:33 PM
Old 06-20-2012
IMHO @drl's solution in post #15 nearly fulfils the requirement.

Reading between the lines, we are again presented with a faulty solution without a definition of the actual problem.

Taking into account Corona688's comment about inodes, this code would be safer on most unix/Linux Operating Systems:
Code:
cp test.log back.log
sed '1,100d' test.log>temp.log 
cat temp.log > test.log


I have used a similar code construct (albeit with grep -v)to remove persistent irrelevant entries from a system log where it was causing unwanted alerts (pending a fix).
Last edited by methyl; 06-20-2012 at 08:55 PM..
This User Gave Thanks to methyl For This Post:
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LEARN ABOUT HPUX

kclog

kclog(1M)																 kclog(1M)

NAME

       kclog - manage kernel configuration log file

SYNOPSIS

       config] string] type] name] [count]
       comment

DESCRIPTION

       is  the	administrative command for the HP-UX kernel configuration log file.  The log file is automatically maintained by all of the kernel
       configuration commands (and Any change to any kernel configuration gets logged to this log file, which is located at Note that this file is
       a  plain text file which can be viewed and manipulated using standard Unix file management commands; exists simply for convenience in find-
       ing particular log file entries.

       Under normal usage, prints the last count entries in the log file.  When one of the options is specified, prints  the  last  count  entries
       that match the specified criteria.  If count is not specified, it defaults to 1.

   Options
       will print all entries matching criteria.  If this option is not specified,
		      will only print the last count entries that match the specified criteria.

       will print only log file entries describing changes to the saved
		      kernel  configuration  named config.  If this option is not specified, will print log file entries describing changes to any
		      saved or running kernel configuration.

       will not print any entries.  Instead,
		      will create a new entry, as if a kernel configuration change had been made, containing the specified comment.   This  option
		      is only allowed for users with appropriate privileges.

       will print only log file entries that contain the given
		      string.

       will print only log file entries that refer to a configuration object
		      (module or tunable) of the given name.

       will print only log file entries that refer to configuration objects
		      of the specified type: or

RETURN VALUE

       returns zero for success.  It returns non-zero and prints a diagnostic message if an error occurs.

EXAMPLES

       To see the last three entries in the log:
       To see the last entry for the tunable
       To see the last five entries for module changes:
       To see all entries for module changes:
       To see the last entry mentioning Aberdeen:
WARNINGS

       The format of the log file may be changed without notice.

       Some configuration changes can be made without using the kernel configuration commands.	No log file entries are made for such changes.

       The log file should not be manually edited.  Doing so may cause to behave unpredictably.

SEE ALSO

       kcmodule(1M), kconfig(1M), kctune(1M), kconfig(5).

       available on

																	 kclog(1M)
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