Question

Is there such a function in PHP that does grep -f filename in unix/linux systems.
If there is none, what PHP functions/tools would help in creating a customised method/function for this. Thanks!

Answer 1

Actually IMHO, I’d say it’s the following:

$result = preg_grep($pattern, file($path));

See preg_grep^­Docs and file^­Docs.

If you need to do that (recursively) over a set of files, there is also glob and foreach or the (Recursive)DirectoryIterator or the GlobIterator^­Docs and not to forget the RegexIterator^­Docs.

---

Example with SplFileObject and RegexIterator:

$stream = new SplFileObject($file); 
$grepped = new RegexIterator($stream, $pattern); 

foreach ($grepped as $line) {
    echo $line;
}

Output (all lines of $file containing $pattern):

$grepped = new RegexIterator($stream, $pattern); 
foreach ($grepped as $line) {
    echo $line;
}

Demo: https://eval.in/208699