cmdutil: replace unix pipe handshake with file lock
The pipe handshake cannot be implemented with Windows detached process, which
disables handle inheritance.
Fix 2/3 for issue421
created new head
merging foo1 and foo to foo1
1 files updated, 1 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
n 0 -2 bar
m 644 14 foo1
copy: foo -> foo1
M bar
M foo1
% removing foo1 and bar
r 0 -2 bar
r 0 -1 foo1
copy: foo -> foo1
R bar
R foo1
% readding foo1 and bar
adding bar
adding foo1
n 0 -2 bar
m 644 14 foo1
copy: foo -> foo1
M bar
M foo1
foo
% reverting foo1 and bar
saving current version of bar as bar.orig
reverting bar
saving current version of foo1 as foo1.orig
reverting foo1
n 0 -2 bar
m 644 14 foo1
copy: foo -> foo1
M bar
M foo1
foo