case:
svn add lib/systemd/system/dropbear@.service
svn: E200009: 'lib/systemd/system/dropbear@.service': a peg revision is not allowed here
analyze:
google:
reference
https://stackoverflow.com/questions/757435/how-to-escape-characters-in-subversion-managed-file-names
solution:
svn add lib/systemd/system/dropbear@.service@
A lib/systemd/system/dropbear@.service