Pattern Matching with Glob: Finding Files by Pattern 5/9

The filepath.Glob function in Go provides a powerful way to find files and directories using pattern matching. The function returns a slice of matching file paths and an error. The error handling is straightforward, with the only error being filepath.ErrBadPattern, which occurs when the pattern syntax is malformed. The function operates on the current working directory by default, but you can specify absolute or relative paths in your patterns. The pattern syntax builds on familiar shell globbing conventions but has specific rules and limitations. Wildcard characters, character classes, and ranges can be used to match file names and extensions. The function doesn't follow symbolic links and only returns paths that actually exist in the file system. The io/fs package introduced the GlobFS interface in Go 1.16, enabling file systems to provide optimized glob implementations. Native glob implementations can dramatically outperform manual traversal, especially on large directory structures. When a file system doesn't implement GlobFS, Go automatically falls back to a directory walking implementation.