smcposix: pass unicode as first argument to array.array
This is an instance where we can safely convert the first argument, rest are
the cases except one where we are using 'c' which is not there in Python 3. So
that needs to be handled differently. This will help in making `hg help` run on
Python 3.
$ cat > unix2mac.py <<EOF
> import sys
>
> for path in sys.argv[1:]:
> data = file(path, 'rb').read()
> data = data.replace('\n', '\r')
> file(path, 'wb').write(data)
> EOF
$ cat > print.py <<EOF
> import sys
> print(sys.stdin.read().replace('\n', '<LF>').replace('\r', '<CR>').replace('\0', '<NUL>'))
> EOF
$ hg init
$ echo '[hooks]' >> .hg/hgrc
$ echo 'pretxncommit.cr = python:hgext.win32text.forbidcr' >> .hg/hgrc
$ echo 'pretxnchangegroup.cr = python:hgext.win32text.forbidcr' >> .hg/hgrc
$ cat .hg/hgrc
[hooks]
pretxncommit.cr = python:hgext.win32text.forbidcr
pretxnchangegroup.cr = python:hgext.win32text.forbidcr
$ echo hello > f
$ hg add f
$ hg ci -m 1
$ python unix2mac.py f
$ hg ci -m 2
attempt to commit or push text file(s) using CR line endings
in dea860dc51ec: f
transaction abort!
rollback completed
abort: pretxncommit.cr hook failed
[255]
$ hg cat f | python print.py
hello<LF>
$ cat f | python print.py
hello<CR>