sftp srver

file server capable of storing files and transfer them as they are encoded or compressed. 1-file Server A –server + client socket/listen/accept/connect/close/open/read/write/mmap/stat Clients will connect to the server. Client can request the server to STORE (i.e. save) a file or LOAD a file. Or LS or receive file list. The server works with one directory. Files stored by one client can be read by all other clients. You may add parameters to the protocol such as file size obtained usingstat or lseek To make things interesting. The server should handle files using mmap/munmap API. Clients should hand files using fread/fwrite [login to view URL] clients and observer Select Migrate your server to act as observer (use either select or poll or pselect orepoll) Files stored by one client can be retrieved by all other client. Special operation Pipe, dup, unix domain sockets Add parameter to receive and send encoded or compressed files (the server can be used to decompress or decode files by storing compressed files and reading them plainly. To read compressed file – use either compress /uncompress or gzip/gunzip or to encode a file use uuencode/uudecode The server should communicate using file descriptor methods (for example message by unix domain sockets) with the compression process. Ensure that only one process exist for each server. (Implement the singleton pattern using unique mktemp per server process Use constructor __attribute__ to ensure your code runs before main. 4. Files that are currently in process should be locked so the client can not download a file while it is being processed The lock should be cleared when processing is done. When a client tries to download a file that is currently being processed and the server tries to access a locked file an error should be reported. Database - Save status to a text file. Decide on format. Allow queries using grep and popen on the past (when was a file added) do not get data using stat! local clients – Support local clients communicating using Unix domain sockets. API remains the same. Please send the compiling project in 1 ZIP or tarred gzipped file containing only should be [login to view URL] or [login to view URL] Please ensure your project compiles with “make all” instruction. Please ensure “make clean” deletes your binary and any cruft. Please add any additional instructions and comments to [login to view URL] file. The code should be self-documented. You may comment critical parts of the To resolve any doubts, your code should compile with the gcc version that comes with your VM (Ubuntu 16.04 gcc version 5.3.1). You may use clang. Don’t use other compilers.