Set OS X cache directory to ~/Library/Caches/[app name]/[profile name] ...

base/file_path.h

 // Copyright (c) 2008 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // FilePath is a container for pathnames stored in a platform's native string
 // type, providing containers for manipulation in according with the
 // platform's conventions for pathnames.  It supports the following path
 // types:
 //
 //                   POSIX            Windows
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   // and BaseName().value() on each child component.
   void GetComponents(std::vector<FilePath::StringType>* components) const;
 
   // Returns true if this FilePath is a strict parent of the |child|. Absolute
   // and relative paths are accepted i.e. is /foo parent to /foo/bar and
   // is foo parent to foo/bar. Does not convert paths to absolute, follow
   // symlinks or directory navigation (e.g. ".."). A path is *NOT* its own
   // parent.
   bool IsParent(const FilePath& child) const;
 
+  // If IsParent(child) holds, appends to path (if non-NULL) the
+  // relative path to child and returns true.  For example, if parent
+  // holds "/Users/johndoe/Library/Application Support", child holds
+  // "/Users/johndoe/Library/Application Support/Google/Chrome/Default", and
+  // *path holds "/Users/johndoe/Library/Caches", then after
+  // parent.AppendRelativePath(child, path) is called *path will hold
+  // "/Users/johndoe/Library/Caches/Google/Chrome/Default".  Otherwise,
+  // returns false.
+  bool AppendRelativePath(const FilePath& child, FilePath* path) const;
+
   // Returns a FilePath corresponding to the directory containing the path
   // named by this object, stripping away the file component.  If this object
   // only contains one component, returns a FilePath identifying
   // kCurrentDirectory.  If this object already refers to the root directory,
   // returns a FilePath identifying the root directory.
   FilePath DirName() const;
 
   // Returns a FilePath corresponding to the last path component of this
   // object, either a file or a directory.  If this object already refers to
   // the root directory, returns a FilePath identifying the root directory;
@@ skipping 116 matching lines @@
 namespace stdext {
 
 inline size_t hash_value(const FilePath& f) {
   return hash_value(f.value());
 }
 
 }  // namespace stdext
 #endif  // COMPILER
 
 #endif  // BASE_FILE_PATH_H_