What is the meaning of the directory specified by '//'?

Question

It can be accessed by typing in 'cd //' at the comand prompt.

I have tried this on mac 10.9.5 and Centos 6. It shows the contents for the root directory. In the prompt it shows '//' for the directory. Is this simply a glitch in the prompt code? I use \w to show the working directory.

http://stackoverflow.com/a/20690872/1870481 – michas Jan 07 '15 at 00:28 — michas, Jan 07 '15 at 00:28

score 0 · Answer 1 · answered Jan 06 '15 at 23:45

0

cd // = Change the shell working directory to the root directoy

answered Jan 06 '15 at 23:45

Muhammad Z

478

1

cd / should do the trick as well. No need to double the slash. – syntaxerror Jan 06 '15 at 23:46

score 0 · Answer 2 · answered Jan 07 '15 at 00:36

Historical compatibility because early versions of Unix used paths such as //host/path.

From the bash FAQ:

E10) Why does cd //' leave $PWD as//'?

POSIX.2, in its description of `cd', says that three or more leading slashes may be replaced with a single slash when canonicalizing the current working directory.

This is, I presume, for historical compatibility. Certain versions of Unix, and early network file systems, used paths of the form //hostname/path to access path' on serverhostname'.

What is the meaning of the directory specified by '//'?

2 Answers2