mpatch: Define Py_ssize_t for old pythons and use it instead of ssize_t.
See also PEP 353.
NOTE: Microsoft compilers (8 or earlier) does not have ssize_t.
#!/bin/sh
hg init
echo 123 > a
hg add a
hg commit -m "first" -d "1000000 0" a
mkdir sub
echo 321 > sub/b
hg add sub/b
hg commit -m "second" -d "1000000 0" sub/b
cat sub/b
hg co 0
cat sub/b 2>/dev/null || echo "sub/b not present"
test -d sub || echo "sub not present"
true