What does dot forward slash forward slash mean (.//)?

Question

I was querrying a server using a command like this:

find ./ -type f -name 'filename"

I got many files starting with

.//library 

or

.//user

What do these things mean?

Answer 1

It doesn't mean much: the pattern that you gave find was ./, and it is simple for find to glue its results onto that path. A double-slash is ignored (treated as a single slash) except that a leading double-slash could have some meaning for some systems. More important, portable programs assume this behavior.

However, you will see this particular behavior only for BSD-derived systems with an old version of find (OSX for example). NetBSD attempted to fix this in their source in 2005; the userland for OSX is older.

Checking "recent" FreeBSD, NetBSD and OpenBSD, none produce this behavior. Linux and Unix (AIX, HPUX, Solaris) likewise do not.

Further reading:

• Mac Terminal “find” command : What does a double slash in the result output mean?

• pgsql: Remove trailing slashes from directories in find command

• find - find files (POSIX)
  

  The find utility shall recursively descend the directory hierarchy from each file specified by path, evaluating a Boolean expression composed of the primaries described in the OPERANDS section for each file encountered. Each path operand shall be evaluated unaltered as it was provided, including all trailing <slash> characters; all pathnames for other files encountered in the hierarchy shall consist of the concatenation of the current path operand, a <slash> if the current path operand did not end in one, and the filename relative to the path operand. The relative portion shall contain no dot or dot-dot components, no trailing <slash> characters, and only single characters between pathname components.

• How does Linux handle multiple consecutive path separators (/home////username///file)?

• On what systems is //foo/bar different from /foo/bar?

Answer 2

The .// means current directory, so .//user in the output indicates file user in the current working directory.

The double // should resolve to a single /, this is true for all systems I've used. Although, POSIX only defines this behavior only for /// (or more), and of course /.

The double // appears because you've used the search path for find as ./, instead of the typical .. Both indicates current working directory, and both are correct. This is find's behavior to append the path in that manner in case of relative paths. Note that, this specific behavior of find is prevalent in only a subset of systems as this answer mentioned, and you one is presumably one of them.

Answer 3

.// is the same as ./

Successive slashes beyond the first have no semantic meaning.