Consistent crashes when copying into Crypto Folder while upload in progress on Linux 4.4

[losvald]

I have reproduced this 4 times by recursively copying ~125MB of medium-sized files (100KB-10MB) into Crypto Folder via rsync tool.

losvald@ubuntu1604 $ psyncgui &   # then log in pCloud and unlock the Crypto Folder
losvald@ubuntu1604 $ rsync -rv /path/to/source /path/to/Crypto/Folder/   # OK
...
losvald@ubuntu1604 $ rsync -rv /path/to/source /path/to/Crypto/Folder/   # REPEAT QUICKLY
rsync: write failed on "/home/losvald/pCloudDrive/Crypto Folder/folder/file.pdf": Transport endpoint is not connected (107)
[1]+  Segmentation fault      (core dumped) psyncgui

In addition, the app crashed several times upon its startup between some of these attempts:

login btn  4 12 12 1 
PSTATUS_CONNECTING 
PSTATUS_UPLOADING 
Segmentation fault (core dumped)

There must be a bug with concurrent writes & reads, perhaps when a new (or same) version of the file that is being uploaded and written concurrently. The simplest way to crash it is by repeatedly executing rsync -r, pausing only a few seconds between consecutive executions.