git clone https://github.com/jbenet/bash-timeout3
mv bash-timeout3/timeout3-v2 /usr/bin/timeout3

# timeout $(sleep 10) at 5 seconds.
> ./timeout3-v1 -t 5 sleep 10
Terminated: 15

> ./timeout3-v1
Synopsis
    timeout3-v1 [-t timeout] [-i interval] [-d delay] command
    Execute a command with a time-out.
    Upon time-out expiration SIGTERM (15) is sent to the process. If SIGTERM
    signal is blocked, then the subsequent SIGKILL (9) terminates it.
    -t timeout
        Number of seconds to wait for command completion.
        Default value: 9 seconds.
    -i interval
        Interval between checks if the process is still alive.
        Positive integer, default value: 1 seconds.
    -d delay
        Delay between posting the SIGTERM signal and destroying the
        process by SIGKILL. Default value: 1 seconds.
As of today, Bash does not support floating point arithmetic (sleep does),
therefore all delay/time values must be integers.

> ./timeout-v2
Synopsis:  timeout3-v2 [-t timeout] [-i interval] [-d delay] command

Executes the command with a time-out.  Upon time-out expiration SIGTERM (15) is
sent to the process.  If SIGTERM signal is blocked, then the subsequent SIGKILL
(9) terminates it.

-t timeout
    Number of seconds to wait for command completion.
    Default value: 5 seconds.  In some practical situations
    this value must be increased (for instance -t 180) to allow
    the command to complete.

-i interval
    Interval between checks if the process is still alive.
    Positive integer, default value: 1 seconds.
    Default value is OK for most situations.

-d delay
    Delay between posting the SIGTERM signal and destroying the process by
    SIGKILL.  Default value: 1 seconds.
    Default value is OK for most situations.

As of today, Bash does not support floating point arithmetic (sleep does),
therefore all time values must be integers.