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Documentation for __dirname is misleading #5525
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When
b.jsis running, it is the currently executing script, nota.js. If you can word it less ambiguously, a docs PR is welcome.- added a commit that references this issue
on Apr 2, 2016 - added 2 commits that reference this issue
on Apr 5, 2016 Please re-open, as the documentation is still (or again?) misleading even in v7.2.1: http://web.archive.org/web/20161207142244/https://nodejs.org/api/globals.html .
To me it looks like
__dirnamealways refers to the script in whose scope it is used, independent of whether that script is currently running. (b doneshows that the script has finished beforeacalls the function it imported.)File
b/b.js:console.log('b start', __dirname); module.exports = function () { console.log('b func', __dirname); }; console.log('b done', __dirname);
File
a/a.js:console.log('a start', __dirname); var b = require('./b/b.js'); console.log('a has required', __dirname); b(); console.log('a done', __dirname);
Output of
nodejs a/a.js:a start /tmp/a b start /tmp/b b done /tmp/b a has required /tmp/a b func /tmp/b a done /tmp/a__dirname always refers to the script in whose scope it is used, independent of whether that script is currently running
"script use" and "script run" have same meaning, how do you think they are different? In your example, all uses of __dirname in b.js occur only when b.js is run. If b.js was not running.... console.log would not be called from b.js.
That said, I kindof like your description, but note that its almost there already: "__dirname isn't actually a global but rather local to each module". Local is of course a reference to scope, but that is not as explicit as it could be. Also, resolved is not so obvious in its meaning.
Would you care to PR a reword?
I think the bigger problem is that the __dirname and __filename docs have diverged, astoundingly, their docs should be almost identical, given that __dirname is path.dirname(__filename)! That they have different verbal gymnastics to describe the same concept should be fixed.
"__dirname isn't actually a global but rather local to each module."
Thanks for showing me, I totally missed that because I only checked the first paragraph earlier.
In your example, all uses of __dirname in b.js occur only when b.js is run.
You're right, and my earlier example even allowed for a much too naive reading of "use". Here's a better one where none of the scripts mention
__dirnameas an identifier in their code:$ head */*.js && echo $'\n== Test it! ==' && nodejs lab/test.js ==> foo/bar.js <== module.exports = function (x) { return eval(x); }; ==> lab/test.js <== var remoteEval = require('../foo/bar.js'), varname; console.log('re:', typeof remoteEval); varname = [ 'me', 'rna', '__di' ].reverse().join(''); console.log('dn:', remoteEval(varname)); == Test it! == re: function dn: /tmp/fooPeople less familiar with closure might really think that some part of bar.js might be running even after the "re:" log call, because they confuse to which point in time the explanation of "currently executing script" applies.
Would you care to PR a reword?
Nope, don't have time to word it as perfectionist as I'd expect for a node PR. ;-)
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on Jul 27, 2026
The documentation for
__dirnamestates that it gives "The name of the directory that the currently executing script resides in."This may be taken to imply that
__dirnamealways refers to the path of the module that was invoked as a script from the command line. However, it actually always produces the path of the current module, no matter where it was required from.Just to clarify: assume I have modules
and
a.jsrequiresb.js. I runnode a.js, andb.jsuses its__dirname, which will refer to thebsubdirectory. The current wording implies that it might actually refer to the directory thata.jsis contained in since that is the "script" that I ran from the command line.