sleepenh | Sleep until a given date with subsecond resolution | Mehr ...
sleepenh is an sleep program for using in shell scripts that need to perform a loop that repeats at a regular time interval, without cumulative errors. . It supports microsecond resolution. . You can also specify the time you need between two calls of sleepenh. . Here follows an usage example to clarify its purpose. This example sends 'A' to ttyS0 every 1.2 seconds. #!/bin/sh # does not wait (or wait 0), just to get initial timestamp TIMESTAMP=`sleepenh 0` while true; do # send the byte to ttyS0 echo -n "A" > /dev/ttyS0; # wait until the required time TIMESTAMP=`sleepenh $TIMESTAMP 1.200`; done . For more details, please read the manpage.