Description:
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I believe stream_get_line() should allow the $length parameter to be optional by allowing a $length of -1 that would read the remaining buffer up to either the $ending delimiter or EOF.

Currently if you pass a $length of 0, the $length defaults to PHP_SOCK_CHUNK_SIZE (8192) in ext/standard/streamsfuncs.c.  If you pass a length of -1, a PHP Warning is generated.

Other 'similar' functions that allow length to be optional or -1 are fgets, stream_get_contents, and file_get_contents.

Also, the manual page for stream_get_line() states that this function is the same fgets() except for the handling of the delimiter - but another difference, at least right now, is that the $length parameter is required in stream_get_line(), but optional in fgets().


Reproduce code:
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<?php
$fp = tmpfile();

fwrite($fp, str_repeat('a', 10000));

fseek($fp, 0);
echo strlen(stream_get_line($fp, 0));

fseek($fp, 0);
echo strlen(stream_get_line($fp, -1));

fclose($fp);


Expected result:
----------------
8192
10000

Actual result:
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8192
Warning: stream_get_line(): The maximum allowed length must be greater than or equal to zero