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22 years ago
I was writing a shell script to get input from a user, however, I needed my script to time out after a certain number of seconds if the user didn't enter enough data. The code below descibes the method I used. It's a little hairy but it does work.



-Ben



#!/home/ben/php/bin/php -q

<?php

//GLOBALS

$RETURN_CHAR = "\n";

$TIMEOUT = 5; //number of seconds to timeout on input

$PID = getmypid();

$CHILD_PID = 0;



//Make sure program execution doesn't time out

set_time_limit(0);



function set_timeout() {

global $PID;

global $CHILD_PID;

global $TIMEOUT;



$CHILD_PID = pcntl_fork();

if($CHILD_PID == 0) {

sleep($TIMEOUT);

posix_kill($PID, SIGTERM);

exit;

}

}



function clear_timeout() {

global $CHILD_PID;

posix_kill($CHILD_PID, SIGTERM);

}



// read_data()

// gets a line of data from STDIN and returns it

function read_data() {



$in = fopen("php://stdin", "r");

set_timeout();

$in_string = fgets($in, 255);

clear_timeout();

fclose($in);

return $in_string;

}



// write_data($outstring)

// writes data to STDOUT

function write_data($outstring) {

$out = fopen("php://stdout", "w");

fwrite($out, $outstring);

fclose($out);

}



while(1) {

write_data("say something->");

$input = read_data();

write_data($RETURN_CHAR.$input);

}



?>
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