reading a block of lines in a file using php

Question

Considering i have a 100GB txt file containing millions of lines of text. How could i read this text file by block of lines using PHP?

i can't use file_get_contents(); because the file is too large. fgets() also read the text line by line which will likely takes longer time to finish reading the whole file.

If i'll be using fread($fp,5030) wherein '5030' is some length value for which it has to read. Would there be a case where it won't read the whole line(such as stop at the middle of the line) because it has reached the max length?

Answer 1

i can't use file_get_contents(); because the file is too large. fgets() also read the text line by line which will likely takes longer time to finish reading the whole file.

Don't see, why you shouldn't be able to use fgets()

$blocksize = 50; // in "number of lines"
while (!feof($fh)) {
  $lines = array();
  $count = 0;
  while (!feof($fh) && (++$count <= $blocksize)) {
    $lines[] = fgets($fh);
  }
  doSomethingWithLines($lines);
}

Reading 100GB will take time anyway.