In unix/linux, any number of consecutive forwardslashes in a path is generally equivalent to a single forwardslash. eg.
$ cd /home/shum $ pwd /home/shum $ cd /home//shum $ pwd /home/shum $ cd /home///shum $ pwd /home/shum
Yet for some reason two forwardslashes at the beginning of an absolute path is treated specially. eg.
$ cd ////home $ pwd /home $ cd /// $ pwd / $ cd // $ pwd // $ cd home//shum $ pwd //home/shum
Any other number of consecutive forwardslashes anywhere else in a patch gets truncated, but two at the beginning will remain, even if you then navigate around the filesystem relative to it.
Why is this? Is there any difference between /... and //... ?