Validating concatenated cin inputs (C++)
 

Hi guys,

I am trying to do a simple, CLi ftp client/server c++ application.

On the client end, once started, the command prompt will be:

ftp>>

just like a regular command line software.

At one point, I am suppose to let use key in the following to transfer file:

basically the above command will just copy a file from client to server.

I achieve that by issuing the following commands:

Where a and b are appropriate variables.

My question is, how can I validate the input, such that, if a user enters only 'put' or 'put fileFromClient' (basically not full commands which consist of the 3 arguements), I can capture it and prompt the user?

Right now, by concatenating cin, the software will keep waiting, such that if I type 'put', hit the return key, the application will appear to be waiting (for the next 2 input).

How can I capture the errornous user input from the moment the user hit the return key? and not let the program wait for the next 3 inputs from user, differentiate by the return key?

I tried using cin.good() but i think I am not getting it right...

anyone? thanks!

ps: this is for a school assignment, but I'm just asking about how can I validate concatenated inputs... not asking help for my work hehe - in case you're wondering ;)

You probably want to read the whole line, using the template method getine(), and then analyse the line for correctness.

you mean cin.getline()?

I tried.. but that way I can't ensure i get 3 inputs on one line, without having the user enter it 3 times separately

well that's why I said you need to check the line that has been read; that would basically mean split it up into tokens, broken down by spaces and see if there are three.

so its not possible to prevent the user from pressing the 'return' key after keying in just 1 argument?

i was looking for possible ways to capture the user's action of entering, say:
This way, the program will still wait for the 3rd argument.

Not unless you intend to use ncurses or similar libraries.