Shell Programming and Scripting

Hi,

I have to write a script and the requirment where using ftp i need to get 8 files from a remote box to local. I know how how to ftp and do get. However i want do a validation after get.

After geting for 8 files, i want to compare the size of the 8 files when it was in remote box with size they have in the local box and depending on that i will dicide if the transfer is suceesfull. Now, i have no i dea how to do this validation.

could anyone please help on this.

checking size is not enough. use a check sum utility like cksum or md5sum and compare hashes

With anything to do with ftp it helps to know which Operating System(s) are involved and whether you have administrative access to both computers to write scripts etc..

Also:
Are these Binary or Text files?
Which end is initiating the ftp and whether it is a "get" or a "put"?

you can do something like this:---

Code:

for old files 
for file in `ls *`
do
cksum $file >> old_file (this is for the old files)
done 
for file in `ls *`
do 
cksum $file >> ftp_file (this is for the ftped files)
done
diff old_file ftp_file

wherever they dont match ... that one is failing. (of if they are not matching it just meas the file has been changed......

Hi methyl,

In response to your queries..
local is unix and remote is windows system and i dont have admin access to the servers.

i will be connecting from unix to windows and will do get for the files and all are binary files.(The files are bigger, takes around 45 t0 60 mins to get).

please suggest.

and also, cksum command is not working in the remote windows system.

set ssh on the remote windows server, and enable the sshd services.

For example, i install CYGWIN to enable the sshd services on windows server.

then set keyless ssh, and scp these files to Unix env.

Just mentioning unix and Windows without flavour or versions is just a bit too vague.

Raw "ftp" is not really suitable for this job but can work well on a good clean private LAN. Beware that many implementations will not work with files larger than 2 Gb or files with fancy filenames.
There is usually much better software than "ftp" but we must assume that you have explored all options.
Even compressing the file prior to transmission gives you a basic verification when uncompressing the file.

Verifying the transfer is more a matter of system design and one would expect a data file to contain checkable data integrity controls.

Always check "ftp" return codes in your script and have provision for timeouts and hangs. It is advisible to transfer a file under a temporary name and only rename the file if the transfer is successful.

I have had variable results when comparing Windows file sizes and unix file sizes for Binary files (it's to do with block padding). The file sizes for Text files will always disagree but the difference can be calculated.