path: add path.isAbsolute(path)

An absolute path will always open the same location regardless of your
current working directory. For posix, this just means path.charAt(0) ===
'/', but on Windows it's a little more complicated.

Fixes joyent/node#5299.

1 files changed, 19 insertions, 0 deletions

diff --git a/doc/api/path.markdown b/doc/api/path.markdown
index fe59134d4..348c7cdae 100644
--- a/doc/api/path.markdown
+++ b/doc/api/path.markdown
@@ -78,6 +78,25 @@ Examples:
     // if currently in /home/myself/node, it returns
     '/home/myself/node/wwwroot/static_files/gif/image.gif'
 
+## path.isAbsolute(path)
+
+Determines whether `path` is an absolute path. An absolute path will always
+resolve to the same location, regardless of the working directory.
+
+Posix examples:
+
+    path.isAbsolute('/foo/bar') // true
+    path.isAbsolute('/baz/..')  // true
+    path.isAbsolute('qux/')     // false
+    path.isAbsolute('.')        // false
+
+Windows examples:
+
+    path.isAbsolute('//server')  // true
+    path.isAbsolute('C:/foo/..') // true
+    path.isAbsolute('bar\\baz')   // false
+    path.isAbsolute('.')         // false
+
 ## path.relative(from, to)
 
 Solve the relative path from `from` to `to`.