Using PHP glob() to Retrieve File Paths with Pattern Matching

In PHP, the glob() function is used to obtain file paths that match a specified pattern. It returns an array of matching file and directory names, making it a handy tool for filesystem operations.

The function signature is:

array glob ( string $pattern [, int $flags = 0 ] )

Parameters:

pattern : The pattern to match. It supports wildcards * (zero or more characters), ? (single character), and character ranges using [] .

flags (optional): An integer that modifies the matching behavior. Common flags include GLOB_BRACE for brace expansion and others for case‑insensitivity, sorting, etc.

Example – match all files in a directory:

$files = glob('path/to/directory/*');

This returns an array containing every file (and sub‑directory) under path/to/directory .

Example – match files with a specific extension:

$files = glob('path/to/directory/*.txt');

The resulting array includes only files ending with .txt .

Example – use brace expansion to match multiple extensions:

$files = glob('path/to/directory/*.{jpg,png}', GLOB_BRACE);

Here GLOB_BRACE enables the {jpg,png} pattern, returning both .jpg and .png files.

Example – recursively match files in sub‑directories:

$files = glob('path/to/directory/**/*', GLOB_BRACE);

The double‑asterisk ** wildcard together with GLOB_BRACE retrieves all files in the specified directory and any of its sub‑directories.

Additional notes: the result may include both files and directories; if no matches are found, glob() returns an empty array. Therefore, callers should check the returned array before processing.

Summary: The glob() function in PHP provides flexible and powerful pattern‑matching for file retrieval. By choosing appropriate patterns and flags, developers can efficiently filter files, but they must handle case sensitivity, directory structures, and empty results appropriately.