my user copy large files, and it's take 10min for file to be copied to the server (/tmp/user/ files/), if in the meantime start my scheduled script, then it will copy a part of some file to server1

my idea is to check the file size twice in a short period (1-2 seconds) of time, then compare, if the size is different then script transfer1.sh will copy it the next time wen is started from cron,

If anyone has an idea how to do this or any other suggestions?

PS another thing, files name will be random, but every file have "TEST" in name.
when my script run there will be about 5 files to transfer, and this control is just for case if one of the files is in copy process, but other files must be transfered to server1

30 * * * * /myscript/transfer1.sh

Code:

#! transfer1.sh  script

cd /tmp/user/files/
for f in `ls *TEST1*` 
#! here i need check if some file is in copy process
do
scp -qB $f user1@server1:/tmp/end/file/$f
rm -rf /tmp/files/$f
done

example, folder contains
/tmp/user/ files/
TEST1.out
TEST2.out
TEST3.out
TEST4.out (example this file is still copying and will bee skiped with transfer to server1)

after transfer delete all files except TEST4.out, that file will bee copyied next time when script is started