I was using command-line PHP to create an interactive script and wanted the user to enter just one character of input - in response a Yes/No question. Had some trouble finding a way to do so using fgets(), fgetc(), various suggestions using readline(), popen(), etc. Came up with the following that works quite nicely:
$ans = strtolower( trim( `bash -c "read -n 1 -t 10 ANS ; echo \\\$ANS"` ) );