On Feb 2 22:28, Corinna Vinschen wrote: > On Feb 2 13:56, Eric Blake wrote: > > On 02/02/2011 01:45 PM, Corinna Vinschen wrote: > > > Works fine for me: > > > > > > $ uname -a > > > CYGWIN_NT-6.1 vmbert7 1.7.7(0.230/5/3) 2010-08-31 09:58 i686 Cygwin > > > $ cd tmp > > > $ mkdir ... > > > $ cd ... > > > $ cp /usr/bin/ls.exe . > > > $ ./ls > > > ls.exe > > > > > > I tried on NTFS, Samba and NFS. > > > > Difference in Windows version? > > > > $ uname -a > > CYGWIN_NT-5.1 LOUNGE 1.7.7(0.230/5/3) 2010-08-31 09:58 i686 Cygwin > > $ pwd > > /tmp/... > > $ ls > > ls.exe > > $ ./ls > > bash: ./ls: No such file or directory > > > > or maybe in bash versions (since I did just upgrade bash from 3.2 to 4.1)? > > No, I'm using tcsh. Apparently you're right, it doesn't work in > XP, but it works in W7. Looks like Microsoft reworked the CreateProcess > call at some point. I have an idea how this might be possible to > workaround. Stay tuned.
Yes, my workaround works. What happens is that XP's CreateProcess calls an internal function at one point which drops leading spaces and trailing dots and spaces from the path, since these were always invalid in DOS paths. And a path component which consists entirely of dots and/or spaces is just invisible from a DOS path perspective. However, if the path to the executable is prepended by the long-path prefix "\\?\", then the CreateProcess function understands the path even on XP since the prefix suppresses the DOS path strangling. However, that's not a generic solution. At one point we deliberately dropped the preceeding "\\?\" because this breaks some native Win32 child processes which are not long-path aware. So, right now, we only keep the long-path prefix if the path is actually longer than MAX_PATH. To fix that, we would have to scan the entire path for path components which contain leading spaces or trailing dots or spaces. That makes fork even slower than it already is. Given that it works fine on Vista and Windows 7 anyway, is it really worth to add this extra code just to support an old OS in a very rare situation? Corinna -- Corinna Vinschen Please, send mails regarding Cygwin to Cygwin Project Co-Leader cygwin AT cygwin DOT com Red Hat -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
