Restarting Interrupted Transfers
File transfers are not restarted if a user aborts the transfer by pressing
CTRL+C, even if Restart is set. This allows interactive aborting of file transfers
at the user's will.
However, file transfers may be manually restarted at a later time after
interruption. This is useful in a situation where the remote location's power has
gone down, and automatic restarts have not succeeded. The manual restart option
allows a user to start a file transfer by setting the restart point of transfer
to the number of bytes that are found in the destination file. Manual restarts
work regardless of the setting of the Restart field.
The manual restart option is indicated by attaching (r) to both the source
file and the destination file in the transfer statement. The TinyTERM Emulator
will then check the remote file's size before starting the transfer. The transfer
will start by seeking to this size on the source file before starting the
transfer, and appending to the remote file. The (r) option is used on both the
source file and the destination file. Using it on a destination file or directory
alone has no effect.
The manual restart facility works only during file transfers that do not
require automatic text conversion. Thus the (r) option may not work if the file was
transferred with Auto Text Conversion turned on. The automatic file restart
facility detects this and restarts from the beginning of the file. In the manual
case using the (r) option, be careful.
Using this option, users or programs could examine a log file and determine
which systems did not receive full files for the preceding transfer, and restart
transfers for them. This method allows script files to be written that will not
fail totally just because one or more specific remote sites have experienced
total failure.