PHP read part of large CSV file - php

Question

I have a large CSV file. Because of memory concerns (with MySQL), I would like to only read a part of it at a time, if possible.
That it's CSV might not be important. The important thing is that it needs to cut with a new line.
Example content:
Some CSV content
that will break
on a line break
This could be my path:
$path = 'path/to/my.csv';
A solution for it could in my mind look like this:
$csv_content1 = read_csv_file($path, 0, 100);
$csv_content2 = read_csv_file($path, 101, 200);
It reads the raw content on line 0-100.
It reads the raw content on line 101-200.
Information
No parsing is needed (just split into content).
The file exists on my own server.
Don't read the whole file into the memory.
I want to be able to do the second read on another time, not on the same run. I accept save temp values like pointers if needed.
I've been trying to read other topics but did not find an exact match to this problem.
Maybe some of these could somehow work?
SplFileObject
fgetcsv
Maybe I can't use $csv_content2 before I've used $csv_content1, because I need to save some kind of a pointer? In that case it's fine. I will read them in order anyway.

Answer 1

After much thinking and reading I finally think I found the solution to my problem. Correct me if this is a bad solution because of memory usage or from other perspectives.
First run
$buffer = part($path_to_file, 0, 100);
Next run
$buffer = part($path_to_file, $buffer['pointer'], 100);
Function
function part($path, $offset, $rows) {
$buffer = array();
$buffer['content'] = '';
$buffer['pointer'] = array();
$handle = fopen($path, "r");
fseek($handle, $offset);
if( $handle ) {
for( $i = 0; $i < $rows; $i++ ) {
$buffer['content'] .= fgets($handle);
$buffer['pointer'] = mb_strlen($buffer['content']);
}
}
fclose($handle);
return($buffer);
}
In my more object oriented environment it looks more like this:
function part() {
$handle = fopen($this->path, "r");
fseek($handle, $this->pointer);
if( $handle ) {
for( $i = 0; $i < 2; $i++ ) {
if( $this->pointer != $this->filesize ) {
$this->content .= fgets($handle);
}
}
$this->pointer += mb_strlen($this->content);
}
fclose($handle);
}