python sleep delay

[jasonrakers]

I am having issues with my script not executing sleep as expected. It appears that my sleep function is being executed first and not within the loop. I am trying to get the command in the loop to run every X seconds.

count = 0
szCommand1 = "set cli pager off"
szCommand2 = "show interface all"
objTab.Screen.Send(szCommand1 + "\r\n")
while (count < 9):
    objTab.Screen.Send(szCommand2 + "\r\n")
    #Wait for X milliseconds
    crt.Sleep(1000), count
    count = count + 1

After selecting "run" script from SecureCRT the script waits for the approximate Sleep value before executing the While loop. I have verified if I change the Sleep value, the time to begin changes accordingly (4000 * 9 = 36 seconds before start, 1000 * 9 = 9 seconds before start, etc.). I am using SecureCRT 6.6.3.

[jdev]

Before you call crt.Screen.Send(), is crt.Screen.Synchronous true, or false?

If crt.Screen.Synchronous is true, then nothing will appear on the screen until you call a crt.Screen.WaitFor*() or a crt.Screen.ReadString().

This means that it may *seem* like your sleep call isn't happening like you desire, only because text won't show up on the screen until the script actually completes. This is by design so that you can make a call to screen.WaitFor*() or screen.ReadString() and have a high degree of confidence that data will not have been received and displayed to the screen between lines of code as the script is executing.

In SecureCRT scripting, you should practice these general "good things":

• Use crt.Screen.Synchronous set to true
• For every crt.Screen.Send() call you make, put in a corresponding crt.Screen.WaitForString(), passing in a value of some text that lets you know that what you sent has completed, and the remote device is ready for another command to be sent. Typically, the text you WaitFor..() or ReadString() to would be the remote shell prompt.
• Don't use crt.Sleep() as a way of synchronizing the script thread with what's happening in the terminal screen. This won't work because the script thread is asynchronous with the terminal screen.
• Read through the SecureCRT Scripting Guide. Even though the primary language used there is VBScript, it contains best practices and information that can pertain to general situations.
• Read through the samples in the Example Scripts "sticky" in the Scripting forum. You can learn a lot and avoid making mistakes that would otherwise lead you to believe there's a bug in the program.
  

--Jake

[jasonrakers]

Originally Posted by jdev

Before you call crt.Screen.Send(), is crt.Screen.Synchronous true, or false?

If crt.Screen.Synchronous is true, then nothing will appear on the screen until you call a crt.Screen.WaitFor*() or a crt.Screen.ReadString().

This means that it may *seem* like your sleep call isn't happening like you desire, only because text won't show up on the screen until the script actually completes. This is by design so that you can make a call to screen.WaitFor*() or screen.ReadString() and have a high degree of confidence that data will not have been received and displayed to the screen between lines of code as the script is executing.

Thanks, it is set to Synchronous. I think I got it now. Thanks for the good info!