POSIX compliance... Post: 302976888

Sponsored Content

Operating Systems OS X (Apple) POSIX compliance... Post 302976888 by wisecracker on Thursday 7th of July 2016 03:56:42 PM

07-07-2016

Registered User

Well I have been experimenting with sleep <secs> to give me a smaller time accurate to about + or - 5mS on this MacBook Pro, OSX 10.7.5.

It would be good enough for the Egg_Timer.sh and passes the ShellCheck test.

It is fully posix compliant with SLEEPs unity seconds timer only.

Boy am I gonna get some flak over this one, (yes I bend the rules a little)... ;o)

Code:

#!/bin/sh
# delay.sh <secs> <millisecs[0-999]>
secs="$1"
millisecs=$( awk -v mS="$2" -v correction=0.94 ' BEGIN { print (( mS / 2 ) * correction ); } ' )
millisecs="${millisecs%.*}"

# Accuracy on my MBP OSX 10.7.5 + or - 5mS of FSD.
mS()
{
	loop=0
	while [ "$loop" -le "$millisecs" ]
	do
		sleep 0
		wait
		loop=$(( loop + 1 ))
	done
}
# Test the mS function only.
time mS
sleep "$secs"

As I quoted in a previous post I could create a resonably accurate timer using 'afplay', 'aplay' or '/dev/dsp'. I might use afplay and make it Apple dedicated...

Thanks Don for the info...

I await the flak... ;o)

wisecracker

View Public Profile for wisecracker

Find all posts by wisecracker

5 More Discussions You Might Find Interesting

1. UNIX for Advanced & Expert Users

sudo & Sox compliance

Hello, I am trying to convince my boss to stop allowing our users to login as root (superuser). Currently our users login to our unix server with their own account, then as needed, they will do an su and put in the root password. This scares me, for a bunch of reasons. Mainly, one is that we...

2. UNIX for Dummies Questions & Answers

man synopsis standard compliance

In different online sources, I found bits and pieces of information about those square and angular brackets and pipes. From what I have read, I can conclude it looks like this: 1. Options outside any brackets are mandatory 2. Options inside these < .. > are mandatory too 3. Options inside ...

3. Cybersecurity

PCI DSS Compliance : Insecure Communication Has Been Detected

From the nessus scanner tool report i got below vulnerability PCI DSS Compliance : Insecure Communication Has Been Detected http://www.tenable.com/plugins/index.php?view=single&id=56208 As per the description given in above link - I am not able to understand How to find insecure port...

4. Red Hat

Looking for PCI Compliance tool for Redhat Lix.

Hi i am in new to Linux world . I have been assigned to a project to find out a tool that will fulfill the PCI compliance for Linux servers for Audit process. anyone have any recommendation on that. Do Rad hat have any native application or plug-ins which we can use for that.

5. HP-UX

Password compliance setting

I need to set password compliance for some servers in my company. However, the requirements are that we need to set different password policies for 3 different user groups within the company. These are : System Users: i.e root, etc Batch/Application Users: oracle, bscs, etc Standard User:...

LEARN ABOUT OPENDARWIN

ntp-wait

ntp-wait(1)							   User Commands						       ntp-wait(1)

NAME

       ntp-wait - Wait for ntpd to stabilize the system clock

SYNOPSIS

       ntp-wait [-flags] [-flag [value]] [--option-name[[=| ]value]]

       All arguments must be options.

DESCRIPTION

       ntp-wait will send at most num-tries queries to ntpd(8), sleeping for secs-between-tries after each status return that says ntpd(8) has not
       yet produced a synchronized and stable system clock.

       ntp-wait will do this quietly, unless the -v flag is provided.  This can be useful at boot time, to delay the  boot  sequence  until  after
       ntpd -g has set the time.

OPTIONS

       -n number, --tries=number
	      Number of times to check ntpd.  This option takes an integer number as its argument.  The default number for this option is:
		   100

		      The maximum number of times we will check ntpd to see if
		      it has been able to synchronize and stabilize the system clock.

       -s secs-between-tries, --sleep=secs-between-tries
	      How  long  to  sleep  between  tries.  This option takes an integer number as its argument.  The default secs-between-tries for this
	      option is:
		   6

		      We will sleep for secs-between-tries after each query
		      of ntpd that returns "the time is not yet stable".

       -v, --verbose
	      Be verbose.

		      By default, ntp-wait is silent.
		      With this option, ntp-wait will provide status information.

       -?, --help
	      Display usage information and exit.

       -!, --more-help
	      Pass the extended usage information through a pager.

       -v [{v|c|n --version [{v|c|n}]}]
	      Output version of program and exit.  The default mode is `v', a simple version.  The `c' mode will print copyright  information  and
	      `n' will print the full copyright notice.

EXIT STATUS

       One of the following exit values will be returned:

       0  (EXIT_SUCCESS)
	      Successful program execution.

       1  (EXIT_FAILURE)
	      The operation failed or the command syntax was not valid.

       70  (EX_SOFTWARE)
	      libopts had an internal operational error.  Please report it to autogen-users@lists.sourceforge.net.  Thank you.

AUTHORS

       Harlan Stenn

NOTES

       This document corresponds to version 4.2.8p13 of NTP.

       This manual page was AutoGen-erated from the ntp-wait option definitions.

ntp (4.2.8p13)							    20 Feb 2019 						       ntp-wait(1)