CVS marks conflicts with in-line «conflict
markers», and prints a C
during an
update. Historically, this has caused problems, because CVS
isn't doing enough. Many users forget about (or don't see) the
C
after it whizzes by on their terminal.
They often forget that the conflict-markers are even present,
and then accidentally commit files containing
conflict-markers.
Subversion solves this problem by making conflicts more tangible. It remembers that a file is in a state of conflict, and won't allow you to commit your changes until you run svn resolved. See «Разрешение конфликтов (при слиянии с чужими изменениями)» for more details.