Get the latest added part of a text file?

Shell Programming and Scripting
1

Hi,
I want to get the latest added part of a text file sent over the network to for analysis. Is there a tool to use to keep track of which part of a text file that has already been analysed so only the "new" lines will be sent and handled? I have checked a few tools but I still don�t know how to solve this. Rsync seems to be able to copy the latest added content of a file in an "incremental way" but I don�t know how to take care of this "incremental content" in a script.
Do you have any ideas?

2

i dnon't know if there is a tool to do what you want. but how about this workaround?

after every analyse make a copy of the file. before every new analyse look for the "diff" and only analyse these differences... this can be done very easy with some lines of shell script code!

hth,
DN2

3

If the data is appended to the file, then perhaps...
(the following is a rough coding; there are issues with spacing and field layouts known)

analyze data as normal
wc -l mydatafile >mydatafile.last

next time to analyze
newcnt=$(wc -l mydatafile)
lastcnt=$(cat mydatafile.last)
newlines=$(echo $newcnt - $lastcnt | bc)

now, a tail command could provide you with the last lines to review

4

Thanks for your help. I will probably use the diff command to get the latest content of the textfile.