01-02-2008
Line deletion help using perl -ne
Hi all,
I know the one liner to delete all the lines in a file which matches a pattern
i.e
perl -i.old -ne 'print unless /pattern/' file
Now i need the perl onliner to delete all the lines which doesnt match the pattern. Also what is the difference between perl -i and perl -i.old.
Does perl -i.old archive the existing file?
Your help in this will be appreciated.
Thanks in advance.
Lijju
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LEARN ABOUT HPUX
evmeventnamematchstr
EvmEventNameMatch(3) Library Functions Manual EvmEventNameMatch(3)
NAME
EvmEventNameMatch(), EvmEventNameMatchStr() - match EVM event name
SYNOPSIS
Library
EVM Support Library
Parameters
pattern The event name pattern sought. The pattern may be any valid event name string. It may include wildcard characters in place
of any component.
event The event containing the event name to be compared against the pattern.
match The result of the match. This operand is set to if the name matches the pattern, and to if it does not.
candidate A character string to be matched against the pattern
DESCRIPTION
Because special matching rules apply when deciding whether a candidate event name matches a known name, the EVM name matching functions
should be used for matching purposes, rather than the C string comparison functions The EVM functions match an event name against a sup-
plied pattern, ignoring any trailing appended components in the candidate name, and correctly matching wildcard characters.
The function takes an event and an event name pattern as input, and returns an indication of whether the event contains a name which
matches the pattern in the match output argument. The pattern may be any valid event name string, and may also include wildcard characters
in place of any component. A wildcard in the pattern matches zero or more name components. A matches exactly one component. A match
occurs if the event name matches all components indicated by the pattern, even if the name has additional trailing elements.
The function performs the same check as but takes a character string as the candidate event name, instead of extracting the candidate event
name from a supplied event.
Both functions set the match output argument to if the name matches the pattern, and to if it does not.
RETURN VALUE
The operation completed without error. The comparison was successful. The value of the match operand indicates whether the name matches
the pattern.
One of the arguments to the function is invalid.
The supplied pattern contains invalid characters.
The supplied event does not contain a name.
ERRORS
The value of is not set.
SEE ALSO
Routines
memccpy(3C), strcat(3C).
Event Management
EVM(5).
EVM Events
EvmEvent(5).
EvmEventNameMatch(3)