A simple wrapper for client-server file transfer.
The folder server1 contains an example of usage for a sequential server while the server2 folder contains the realization of a concurrent server based on processes.
Realization of a concurrent server based on threads is also possible.
The code contains references to sockwrap.c and errlib.c created by Stevens.

Client file request:

|G|E|T| |<filename>|CR|LF|

Client quit:

|Q|U|I|T|CR|LF|

Server error:

|-|E|R|R|CR|LF|

Server send the following message after the request (if everything is ok):

|+|O|K|CR|LF|B1|B2|B3|B4|T1|T2|T3|T4|<File content>|

Where the sequence B1 B2 B3 B4 is the byte dimension of the file (on 4 bytes) and T1 T2 T3 T4 is the file timestamp.

Compile

• client:
  

gcc -std=gnu99 -o client client1/*.c *.c -Iclient1 -lpthread -lm

• sequential server:
  

gcc -std=gnu99 -o server server1/*.c *.c -Iserver1 -lpthread -lm

• concurrent server:
  

gcc -std=gnu99 -o server server2/*.c *.c -Iserver2 -lpthread -lm

Run

• client:
  

./client1 <server_addr> <server_port> <file1> <file2> ... <filen>

• server:
  

./server1 <server_port>

./server2 <server_port>