Обсуждение: mklink of pg_standby
Hi Simon, and Dave,Magnus. About pg_standby, a link option cause a problem in windows(XP and 2k,2k3). It is because the call of mklink is needed. Then, they are the new programs of VISTA and 2008. It is CreateSymbolicLink of API of kernel32.lib is equipped with mklink. http://msdn2.microsoft.com/en-us/library/aa363866.aspx Therefore, I considered whether it should correspond by the 'Junction' or the 'Hard Link' this way and that. However, The addition thought that it was not desirable by the reason of the process of evolution functional pg_standby. A copy function is no problem. However, I think that it is necessary to write it to a document in order to avoid a user's confusion. probably, has that no source code corrects. to Dave,and Magnus. You can do more honest suggestion.:-) Regards, Hiroshi Saito
On Mon, 2008-01-21 at 15:36 +0900, Hiroshi Saito wrote: > Hi Simon, and Dave,Magnus. > > About pg_standby, a link option cause a problem in windows(XP and 2k,2k3). > It is because the call of mklink is needed. Then, they are the new programs of > VISTA and 2008. It is CreateSymbolicLink of API of kernel32.lib is equipped > with mklink. > http://msdn2.microsoft.com/en-us/library/aa363866.aspx > > Therefore, I considered whether it should correspond by the 'Junction' or the 'Hard > Link' this way and that. However, The addition thought that it was not desirable > by the reason of the process of evolution functional pg_standby. A copy function > is no problem. However, I think that it is necessary to write it to a document in > order to avoid a user's confusion. probably, has that no source code corrects. Hi Hiroshi, pg_standby uses "mklink" which defaults to creating symbolic links on Win2003 and Win2008: http://technet2.microsoft.com/windowsserver2008/en/library/0ce4df22-2dbc-48fc-9c16-b721ae85f8571033.mspx?mfr=true I think you're referring to the point that "mklink" is not available for XP and 2k. The API call you give is limited to Windows Vista and later, so doesn't really help us get any closer. If anybody has a suggestion, I'd be happy to implement, though I don't have a test rig for Windows. -- Simon Riggs 2ndQuadrant http://www.2ndQuadrant.com
On Mon, Jan 21, 2008 at 03:36:29PM +0900, Hiroshi Saito wrote: > Hi Simon, and Dave,Magnus. > > About pg_standby, a link option cause a problem in windows(XP and 2k,2k3). > It is because the call of mklink is needed. Then, they are the new programs > of VISTA and 2008. It is CreateSymbolicLink of API of kernel32.lib is > equipped with mklink. > http://msdn2.microsoft.com/en-us/library/aa363866.aspx > > Therefore, I considered whether it should correspond by the 'Junction' or > the 'Hard Link' this way and that. However, The addition thought that it > was not desirable by the reason of the process of evolution functional > pg_standby. A copy function is no problem. However, I think that it is > necessary to write it to a document in order to avoid a user's confusion. > probably, has that no source code corrects. > > to Dave,and Magnus. > You can do more honest suggestion.:-) Junctions only work for directories, not for files. In theory, you should be able to use mklink to create a hardlink on previous versions of Windows, but I'm not sure if it'll work. But we want symlinks here, not hardlinks, and they are simply not supported on earlier versions of Windows. It is alerady documented that it doesn't work on Windows prior to Vista. I think this is fine. What we could add is a specific version check to pg_standby to have it emit a "not supported on this windows version" error if it's not supported. But I think that's overkill - it will still fail, and it's well documented that it's not *supposed* to work. //Magnus
On Mon, Jan 21, 2008 at 07:33:57AM +0000, Simon Riggs wrote: > On Mon, 2008-01-21 at 15:36 +0900, Hiroshi Saito wrote: > > Hi Simon, and Dave,Magnus. > > > > About pg_standby, a link option cause a problem in windows(XP and 2k,2k3). > > It is because the call of mklink is needed. Then, they are the new programs of > > VISTA and 2008. It is CreateSymbolicLink of API of kernel32.lib is equipped > > with mklink. > > http://msdn2.microsoft.com/en-us/library/aa363866.aspx > > > > Therefore, I considered whether it should correspond by the 'Junction' or the 'Hard > > Link' this way and that. However, The addition thought that it was not desirable > > by the reason of the process of evolution functional pg_standby. A copy function > > is no problem. However, I think that it is necessary to write it to a document in > > order to avoid a user's confusion. probably, has that no source code corrects. > > Hi Hiroshi, > > pg_standby uses "mklink" which defaults to creating symbolic links on > Win2003 and Win2008: > > http://technet2.microsoft.com/windowsserver2008/en/library/0ce4df22-2dbc-48fc-9c16-b721ae85f8571033.mspx?mfr=true > > I think you're referring to the point that "mklink" is not available for > XP and 2k. I assume you actually maen Vista + 2008? Symlinks aren't supported on Win2k3 AFAIK, and that page certainly says nothing about them. Plus, none of my 2k3 machines appear to have mklink.exe :-P //Magnus
Hi. ----- Original Message ----- From: "Magnus Hagander" <magnus@hagander.net> > Junctions only work for directories, not for files. > > In theory, you should be able to use mklink to create a hardlink on > previous versions of Windows, but I'm not sure if it'll work. But we want > symlinks here, not hardlinks, and they are simply not supported on earlier > versions of Windows. > > It is alerady documented that it doesn't work on Windows prior to Vista. I > think this is fine. What we could add is a specific version check to > pg_standby to have it emit a "not supported on this windows version" error > if it's not supported. But I think that's overkill - it will still fail, > and it's well documented that it's not *supposed* to work. Yeah, vote +1:-) Probably, the equipment which is not Symbolic Link is needed in order to correspond to XP and 2K. It is hard to use rather than 'SymbolicLink'. It will be enough if notice are written to a document. Regards, Hiroshi Saito
On Mon, Jan 21, 2008 at 10:11:52PM +0900, Hiroshi Saito wrote: > Hi. > > ----- Original Message ----- > From: "Magnus Hagander" <magnus@hagander.net> > > > >Junctions only work for directories, not for files. > > > >In theory, you should be able to use mklink to create a hardlink on > >previous versions of Windows, but I'm not sure if it'll work. But we want > >symlinks here, not hardlinks, and they are simply not supported on earlier > >versions of Windows. > > > >It is alerady documented that it doesn't work on Windows prior to Vista. I > >think this is fine. What we could add is a specific version check to > >pg_standby to have it emit a "not supported on this windows version" error > >if it's not supported. But I think that's overkill - it will still fail, > >and it's well documented that it's not *supposed* to work. > > Yeah, vote +1:-) > Probably, the equipment which is not Symbolic Link is needed in order > to correspond to XP and 2K. It is hard to use rather than 'SymbolicLink'. > It will be enough if notice are written to a document. The notice is *alraedy* in the documentation. http://www.postgresql.org/docs/8.3/static/pgstandby.html has: "-l will not work on versions of Windows prior to Vista." //Magnus
Hi. From: "Magnus Hagander" <magnus@hagander.net> >> Yeah, vote +1:-) >> Probably, the equipment which is not Symbolic Link is needed in order >> to correspond to XP and 2K. It is hard to use rather than 'SymbolicLink'. >> It will be enough if notice are written to a document. > > The notice is *alraedy* in the documentation. > http://www.postgresql.org/docs/8.3/static/pgstandby.html > has: > "-l will not work on versions of Windows prior to Vista." Ugaa, sorry this noise. , I had overlooked it.