Re: Current working directory and multi-threaded environments

On Wed, Mar 15, 2000 at 08:32:43PM +0200, Andi Gutmans wrote: > Hi, > > I want to layout a way to fix the issue of the chdir()'s in PHP which > prevents PHP from working properly in multi-threaded environments. > > The solution will probably include doing one getcwd() on startup and > setting a per-request variable with its value. > > >From that point on we'll never use chdir() and getcwd() anymore but > something like virtual_chdir() and virtual_getcwd() which will behave the > same way but will not really change the current working directory but will > adjust the per-request cwd string. Additionally to this, we need a function which converts a relative path to an absolute path. Otherwise, every user of the virtual_* functions will have to reinvent the wheel. Alternatively, we could provide wrappers around system calls. The wrappers would convert the arguments passed to them and call the real system function. I don't like this particularly, because there are many 3rd party library functions which we cannot cover all. What do you think? > Of course, the file opening functions will be changed to use the new > functions instead of the original ones and then we should have pretty > decent virtual current working directories. > > Comments? Does anyone have a better solution or see problems with this > one? > > BTW, any idea if Apache changes the current working directory per-request? I grepped through Apache 2.0 yesterday and there don't seem to be any request-related getcwd()s or chdir()s. > I'm not sure if I need to do the real getcwd() per-request or if doing it > on PHP startup once is good enough. Why should a threaded web server change its per-process work directory? - Sascha