Need a PING function

[rdonnay]

For several years, I have been using the below code to ping addresses.

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RunShell("/C ping.exe -n 1 -w 1 &cLocalIPaddress2 >ping.txt",,.f.,.t.) 

This is in a customer application that talks to a piece of hardware containing 2 microprocessors, each bound to a different IP address.
We never know what the IP addresses will be because they are leased addresses.
This requires pinging every address on a subnet until we find the Rabbit microprocessors.

Sometimes this takes a long time because using Runshell is a slow process.
Has anyone found a better solution than the PING command?

[Cliff Wiernik]

Does this win32api function work.

https://msdn.microsoft.com/en-us/librar ... S.85).aspx

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IcmpSendEcho function

The IcmpSendEcho function sends an IPv4 ICMP echo request and returns any echo response replies. The call returns when the time-out has expired or the reply buffer is filled.
Syntax
C++


DWORD IcmpSendEcho(
  _In_     HANDLE                 IcmpHandle,
  _In_     IPAddr                 DestinationAddress,
  _In_     LPVOID                 RequestData,
  _In_     WORD                   RequestSize,
  _In_opt_ PIP_OPTION_INFORMATION RequestOptions,
  _Out_    LPVOID                 ReplyBuffer,
  _In_     DWORD                  ReplySize,
  _In_     DWORD                  Timeout
);

Para

[Cliff Wiernik]

Found this for VB, appears to be standard win32.dll function call setup.

Declaration:

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Private Declare Function GetRTTAndHopCount Lib "iphlpapi.dll" _
        (ByVal lDestIPAddr As Long, _
         ByRef lHopCount As Long, _
         ByVal lMaxHops As Long, _
         ByRef lRTT As Long) As Long
         
Private Declare Function inet_addr Lib "wsock32.dll" _
        (ByVal cp As String) As Long

Code

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Public Function SimplePing(sIPadr As String) As Boolean

    ' Based on an article on 'Codeguru' by 'Bill Nolde'
    ' Thx to this guy! It 's simple and great!

    ' Implemented for VB by G. Wirth, Ulm,  Germany
    ' Enjoy!
    
    Dim lIPadr      As Long
    Dim lHopsCount  As Long
    Dim lRTT        As Long
    Dim lMaxHops    As Long
    Dim lResult     As Long
    
    Const SUCCESS = 1
    
    lMaxHops = 20               ' should be enough ...
    
    lIPadr = inet_addr(sIPadr)
    
    SimplePing = (GetRTTAndHopCount(lIPadr, lHopsCount, lMaxHops, lRTT) = SUCCESS)
    
End Function

[WernerSt]

Roger,
I use this function to check the internet to my internet address for example. I think this dll performs a ping:

function isDBFIBU
return InternetCheckConnectionA( "HTTP://WWW.DBFIBU.DE" + c_NULL, 1, 0 ) > 0

DLLFUNCTION InternetCheckConnectionA(Url,dwFlags,nSize) using STDCALL from WININET.DLL

[rdonnay]

Thanks for all your suggestions.

I will give them a try and report my findings.