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Top Forums UNIX for Dummies Questions & Answers Understanding the concept behind subshells Post 302888850 by RudiC on Monday 17th of February 2014 05:51:58 PM
Old 02-17-2014
Posting your /etc/passwd here wouldn't be a good idea.
Using several grep processes to read some fields from it is no good idea either. And assigning fields to enumerated variables can exceed the number of variables if you don't exactly know how many data lines you are going to read. Grepping for 5000 just along the line may not be specific enough; unwanted fields may fulfill this condition and give false hits.
Why don't you try sth like
Code:
while IFS=: read UN X UID GID USER REST; do echo Username: $UN, $UID, $USER; done </etc/passwd

 

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STREAM_SET_TIMEOUT(3)							 1						     STREAM_SET_TIMEOUT(3)

stream_set_timeout - Set timeout period on a stream

SYNOPSIS
bool stream_set_timeout (resource $stream, int $seconds, [int $microseconds]) DESCRIPTION
Sets the timeout value on $stream, expressed in the sum of $seconds and $microseconds. When the stream times out, the 'timed_out' key of the array returned by stream_get_meta_data(3) is set to TRUE, although no error/warning is generated. PARAMETERS
o $stream - The target stream. o $seconds - The seconds part of the timeout to be set. o $microseconds - The microseconds part of the timeout to be set. RETURN VALUES
Returns TRUE on success or FALSE on failure. CHANGELOG
+--------+---------------------------------------------------+ |Version | | | | | | | Description | | | | +--------+---------------------------------------------------+ | 4.3.0 | | | | | | | As of PHP 4.3, this function can (potentially) | | | work on any kind of stream. In PHP 4.3, socket | | | based streams are still the only kind supported | | | in the PHP core, although streams from other | | | extensions may support this function. | | | | +--------+---------------------------------------------------+ EXAMPLES
Example #1 stream_set_timeout(3) example <?php $fp = fsockopen("www.example.com", 80); if (!$fp) { echo "Unable to open "; } else { fwrite($fp, "GET / HTTP/1.0 "); stream_set_timeout($fp, 2); $res = fread($fp, 2000); $info = stream_get_meta_data($fp); fclose($fp); if ($info['timed_out']) { echo 'Connection timed out!'; } else { echo $res; } } ?> NOTES
Note This function doesn't work with advanced operations like stream_socket_recvfrom(3), use stream_select(3) with timeout parameter instead. This function was previously called as set_socket_timeout(3) and later socket_set_timeout(3) but this usage is deprecated. SEE ALSO
fsockopen(3), fopen(3). PHP Documentation Group STREAM_SET_TIMEOUT(3)
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