Re: File seek

You're not error checking

$ perl -le " open my($fh), 1 or die$!; seek $fh, 1,0 or die$!; "

$ perl -le " open my($fh), 1 or die$!; seek $fh, -1,0 or die$!; "
Invalid argument at -e line 1.
[download]

You have the file size, if you want to seek to -500, do some math :)

Comment on Re: File seek Download Code

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Re^2: File seek by Anonymous Monk on Feb 25, 2013 at 10:37 UTC
I am seeking to -500 as i know that the keyworn(<run>)wil be in last 500 characters	[reply]
Re^3: File seek by Anonymous Monk on Feb 25, 2013 at 10:45 UTC
I am seeking to -500 as i know that the keyworn(<run>)wil be in last 500 characters no you aren't, seek doesn't take negative offsets, like the error message I showed says	[reply]
Re^4: File seek by johngg (Canon) on Feb 25, 2013 at 11:55 UTC
From the documentation The values for WHENCE are 0 to set the new position in bytes to POSITION; 1 to set it to the current position plus POSITION; and 2 to set it to EOF plus POSITION, typically negative. I suspect your error message is because you are trying to `seek` to a negative offset from the beginning of the file. Cheers, JohnGG	[reply] [d/l]
Re^4: File seek by vinoth.ree (Monsignor) on Feb 25, 2013 at 11:50 UTC
`seek (file, distance, from)` As you can see, seek requires three arguments: file: which is the file variable representing the file in which to skip distance: which is an integer representing the number of bytes (characters) to skip from:which is either 0, 1, or 2 0 - The number of bytes to skip from beginning of the file. 1 - The number of bytes to skip from current location of the file. 2 - The number of bytes to skip from end of the file. `seek(CONFIRMEDOUTPUTFILE, -500, 2);` The above line skip backward 500 bytes from the end of the file.	[reply] [d/l] [select]