Netcat frontend - please help

[Piotrek]

Hello,

I have a task to write a ftp client using a compiled version of linux
netcat. I figures this would be a good way to learn perl

What I need to do is to take the default input and output from a
launched netcat prog. and make a frontend.

I need to do something like (in pseudo): if (INPUT == "331 Password
required for xxx") { print("PASS xxx1"); } , make a command prompt and
some commands like if (COMMAND == "ls") { print("DIR"); }.

Can You tell me how to do that?

Especially how to reditect the input/output and script it.

Thank You!

 

[Ben Morrow]

Quoth (e-mail address removed) (Piotrek):

I have a task to write a ftp client using a compiled version of linux
netcat. I figures this would be a good way to learn perl

What I need to do is to take the default input and output from a
launched netcat prog. and make a frontend.

I need to do something like (in pseudo): if (INPUT == "331 Password
required for xxx") { print("PASS xxx1"); } , make a command prompt and
some commands like if (COMMAND == "ls") { print("DIR"); }.

If this isn't homework, use Net::FTP instead.
Otherwise, do your work yourself.

Ben

 

[Ian Wilson]

Hello,

I have a task to write a ftp client using a compiled version of linux
netcat. I figures this would be a good way to learn perl

I'd have thought it was better to use one of Perl's FTP modules. To me,
this would be a more natural way of using Perl. Search CPAN for FTP.

Otherwise program Sockets directly, it's not that hard in Perl. The
Camel book used to have examples of this.

What I need to do is to take the default input and output from a
launched netcat prog. and make a frontend.

There is already a program that does this kind of thing, called Expect.
In addition, Perl has an "Expect" module.

I need to do something like (in pseudo): if (INPUT == "331 Password
required for xxx") { print("PASS xxx1"); } , make a command prompt and
some commands like if (COMMAND == "ls") { print("DIR"); }.

Can You tell me how to do that?

I imagine the main complication will be timeouts and trapping & handling
of exceptions & errors. Expect makes this easier. I find that dialogues
with interactive programs often seem much more event driven than linear.

Especially how to reditect the input/output and script it.

Have you looked in "Learning Perl" by O'Reilly, or their "Perl CookBook"?

If I was a Perl neophyte, I'd find a better problem for a learning
exercise than this one. YMMV.