• Work around broken sz

    From Rob Swindell@1:103/705 to GitLab note in main/sbbs on Mon Mar 15 12:12:36 2021
    https://gitlab.synchro.net/main/sbbs/-/commit/581087f329a38dc7130b0c760413a7214757cad7#note_1708

    Just to clarify, "sz --ymodem" was sending the empty/termination block, but the server (SBBS) was flushing its output buffer before the block could be placed into the TCP transmit buffers (the rioctl(IOFB) call in download.cpp).No change to SyncTERM should be needed to resolve this issue.
    --- SBBSecho 3.13-Linux
    * Origin: Vertrauen - [vert/cvs/bbs].synchro.net (1:103/705)