Re: Detecting Last line of a file

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Re^2: Detecting Last line of a file by tphyahoo (Vicar) on Jun 18, 2005 at 15:38 UTC
Yeah, this EOF seems like a good way to go. It's addressed in some, but not all (eg, not the activestate) perlfaq5: "How do I change one line in a file/delete a line in a file/insert a line in the middle of a file/append to the beginning of a file? ..... The following code snippet deletes the last line of a file without making a copy or reading the whole file into memory: `open (FH, "+< $file"); while ( <FH> ) { $addr = tell(FH) unless eof(FH) } truncate(FH, $addr);"` [download] Presumably you can modify this to do things other than deleting. Hope this helps! Or, you could do like the most recent perlfaq5 suggests and use Tie::File: "How do I change one line in a file/delete a line in a file/insert a line in the middle of a file/append to the beginning of a file? Use the Tie::File module, which is included in the standard distribution since Perl 5.8.0."	[reply] [d/l]

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Re^2: Detecting Last line of a file
by tphyahoo (Vicar) on Jun 18, 2005 at 15:38 UTC

"How do I change one line in a file/delete a line in a file/insert a line in the middle of a file/append to the beginning of a file?

.....

The following code snippet deletes the last line of a file without making a copy or reading the whole file into memory:

        open (FH, "+< $file");
        while ( <FH> ) { $addr = tell(FH) unless eof(FH) }
        truncate(FH, $addr);"
[download]

Or, you could do like the most recent perlfaq5 suggests and use Tie::File:

"How do I change one line in a file/delete a line in a file/insert a line in the middle of a file/append to the beginning of a file? Use the Tie::File module, which is included in the standard distribution since Perl 5.8.0."

[reply]
[d/l]