pathhandling

Path handling refers to the set of techniques and APIs used to manipulate path strings in software, including filesystem paths and URL paths. It encompasses parsing, joining, normalizing, resolving, and validating paths, as well as querying components such as directory, file name, and extension.

Common path types include filesystem paths, which identify locations on a storage volume, and URL paths, which identify resources within a web context. In web frameworks, virtual or routing paths may also be considered.

Core operations include joining multiple path segments, normalizing to remove redundant separators and resolve special segments like . and .., resolving symbolic links or mount points, and extracting components (parent directory, base name, extension). Path resolution may be absolute or relative, and support for path normalization varies by platform.

Platform differences: POSIX systems use forward slashes and case-sensitive paths; Windows uses backslashes and may treat paths case-insensitively and support drive letters. Cross-platform code often uses library abstractions that translate between representations.

APIs: languages offer dedicated path libraries—Python's pathlib and os.path, Java's NIO Paths, Node.js path, Go path/filepath, Rust std::path, C++ std::filesystem, etc.—that provide portable helpers for joining, normalizing, and inspecting paths.

Security and correctness: improper path handling can lead to directory traversal vulnerabilities or misinterpretation of relative paths. Practices include canonicalization, using library calls, validating input against allowed roots, and avoiding manual string concatenation. Be mindful of encoding, especially with URL paths and percent-encoding.