Question

I’m at a loss as to how I could build a loop to pdftotext and entire directory through a shell_exec() statement.

Something like :

$pdfs = glob("*.pdf");

foreach($pdfs as $pdfs) {
    shell_exec('pdftotext '.$pdfs.' '.$pdfs'.txt');
}

But I’m unsure how I can drop the .pdf extension the 2nd time I call $pdfs in my shell_exec() statement and replace that with .txt

Not really sure this loop is correct either….

Answer 1

Try

foreach(glob("*.pdf") as $src) {

  // Manually remove file extension because glob() may return a dir path component
  $parts = explode('.', $src);
  $parts[count($parts) - 1] = 'txt';
  $dest = implode('.', $parts);

  // Escape shell arguments, just in case
  shell_exec('pdftotext '.escapeshellarg($src).' '.escapeshellarg($dest));

}

Basically, loop the PDF files in the directory and execute the command for each one, using just the name component of the file name (extracted with pathinfo())^{see edit} for the output file (so test.pdf becomes test.txt).

Using the result of glob() directly in foreach easily avoids the variable naming collision you had in the code above.

EDIT

I have change the above code to manually remove the file extension when generating the output file name. This is because glob() may return a directory component of the path strings, as well as just a file name. Using pathinfo() or basename() will strip this off, and since we know that a . will be present in the file name (the rule passed to glob() dictates this) we can safely remove everything after the last one. I have also added escapeshellarg() for good measure – it is highly unlikely (if not impossible) that a file name that already exists would fall foul of this, but it is best to be safe.