Hi to all,

I need some help with the following C program that runs on Linux:

1) The server part:

The program is invoked via console where parameters are passed to it. The parameters will include a path to a file (of type .sh) and the ip addresses to which to send that file. The program has to wait for acknowledment from the destination host that the latter has received it, and then terminate.


2) The client part

The program runs in the background as a daemon and waits for any new packets destined for it. When it receives the file, it executes it. It also has to send an acknowledment of receipt to sender host.

How can I do that?

Any help will be much appreciated..

Warm regards,
Visham

You can easily do those in C. Try searching on google for "Beej's Guide to Network Programming Using Internet Sockets".

Sounds like homework and if it's homework, you would have covered this material in class had you turned up/not slept through it.

So I'm going to be annoying and say use scp it's already written!!!11one

No it's my own work..I wanted s.o to guide me to some program source code that ressembles this program..I'm not asking s.o to do it for me..just a starting point on which I can build, that's all.

I did loads of searches for simple file transfer programs but no success, esp when it comes to the file transfer and daemon part..

So If s.o knows of some program that ressembles this, pls give me the link. any tips with regard to the writing of this program are also very much welcomed.

Warm regards,
Visham

Well in that case, you could take a look at scp seriously. It implements a lot of encryption that you wouldn't need but basically it's a client program that communicated with sshd to transfer files

It's obvious that you will never find something that exactly does what you want.

Some examples that might get you going with regards to socket programming.

To run something in the background (daemon), have a look at fork().

BTW, your question fits better in LinuxQuestions.org > Forums > Non-*NIX Forums > programming and it now has been moved

Moved: This thread is more suitable in Programming and has been moved accordingly to help your thread/question get the exposure it deserves.

Very interesting link. Thanks .

Best wishes,
Michael

Hi to all,

MAny thx for the replies and very useful links..as far I have read and searched, I've never come across program that do file transfer, say, a .txt file, via sockets. I've only seen strings being sent. How do I "convert" that .txt file into packets?

Warm regards,
Visham

The networking subsystem in the OS kernel (in this case, the TCP/IP stack) does that for you. You just read() the bytes you want to send(), literally. Play with it. I remember reading Beej's guide some years ago. It's enough to get you going. Read the FAQ's too: Sockets, TCP/IP, Raw sockets.

PS: Note that with UDP, each sendto() maps to one IP packet, possibly fragmented using IP fragmentation (which is different from fragmenting data into various IP packets)

Data is data, it does not matter if it's a text file or user input or ...
If it's a textfile, you can read a file with e.g. fgets (reads a line at a time). Next send it over the socket; the number of bytes is the length of the string.

Oh ja, be aware of the string terminator. Either you send it (the length will be one byte more, or you handle it at the receiving end).

tcl and perl have quite simple socket implementations to get you started.
look at netcat too.