/usr/lib/php5/php5-fpm-reopenlogs is in php5-fpm 5.6.33+dfsg-0+deb8u1.
This file is owned by root:root, with mode 0o755.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 | #!/bin/sh
CONFFILE=/etc/php5/fpm/php-fpm.conf
[ -r /etc/default/php5-fpm ] && . /etc/default/php5-fpm
CONF_PIDFILE=$(sed -n 's/^[[:space:]]*pid[[:space:]]*=[[:space:]]*//p' $CONFFILE)
PIDFILE=${CONF_PIDFILE:-/run/php5-fpm.pid}
[ -r "$PIDFILE" ] && kill -USR1 $(cat "$PIDFILE") > /dev/null
exit 0
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