Computer Systems: A Programmer's Perspective (3rd Edition)
3rd Edition
ISBN: 9780134092669
Author: Bryant, Randal E. Bryant, David R. O'Hallaron, David R., Randal E.; O'Hallaron, Bryant/O'hallaron
Publisher: PEARSON
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Chapter 12, Problem 12.27HW
Some network
FILE *fpin, *fpout;
fpin = fdopen(sockfd, "r");
fpout = fdopen(sockfd, "w”);
When the server finishes interacting with the client, close both streams as follows:
fclose(fpin);
fclose(fpout);
However, if you try this approach in a concurrent server based on threads, you will create a deadly race condition. Explain.
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Using client-server socket programming, implement a multi-threaded server that
returns to the client the synonym of a word as stored in a dictionary. The client
should prompt the user for a word, reads the word from the screen and sends it to
the server and waits for response from the server. Once the client gets the synonym
of the word, it should print the word and its synonym on the screen and prompt for
another word. This should continue until the user enters the characters @ to quit.
Example:
>>> python TCPClient.py
Input a word: weak
weak ==> frail
Input a word: fair
fair ==> just
Input a word: @
Notes:
1) A file that contains some words and their synonyms is provided
2) In the server code, read the file to a global python dictionary object
engDict = {} # empty dictionary object
with open('dictionary.txt') as f: # open the file
for line in f:
tok = line.split()
engDict[tok[0]] = tok[1]
print(engDict)
3) Here is a Skelton of the server
[some code here ]
class…
Using client-server socket programming, implement a multi-threaded server that returns to the client the synonym of a word as stored in a dictionary. The client should prompt the user for a word, reads the word from the screen and sends it to the server and waits for response from the server. Once the client gets the synonym of the word, it should print the word and its synonym on the screen and prompt for another word. This should continue until the user enters the characters @ to quit. Example: >>> python TCPClient.py Input a word: weak weak ==> frail Input a word: fair fair ==> just Input a word: @ Notes: 1) A file that contains some words and their synonyms is provided 2) In the server code, read the file to a global python dictionary object engDict = {} # empty dictionary object with open('dictionary.txt') as f: # open the file for line in f: tok = line.split() engDict[tok[0]] = tok[1] print(engDict) 3) Here is a Skelton of the server [some code here ] class…
Need help to implement networking in python
Server.py
Load data from file This option will ask the user for a fully qualified path and will load a JSON file containing the information for users and pending messages. The format of the JSON file will be defined based on your implementation and it will the same used to save the data into file (menu option #4).
Functionalities the server must provide: 1)
User Sign Up: adds a user identified by a phone number to the system.
a) Protocol: USR|username|password|display_name
b) Response: 0|OK for success. 1| for an error.
c) The server should validate that the username does not exist
2) User Sign In: verify user credentials
a) Protocol: LOG|username|password
b) Response: i) 0|OK → the credentials are correct.
ii) 1|Invalid Credentials iii) 2|Already Logged In → in case that the user is logged in from another client.
c) This will help the server knowing which user is connected.
d) The server should keep a list of connected clients, which should…
Chapter 12 Solutions
Computer Systems: A Programmer's Perspective (3rd Edition)
Ch. 12.1 - Prob. 12.1PPCh. 12.1 - Prob. 12.2PPCh. 12.2 - Practice Problem 12.3 (solution page 1036) In...Ch. 12.2 - Practice Problem 12.4 (solution page 1036) In the...Ch. 12.4 - Prob. 12.5PPCh. 12.4 - Prob. 12.6PPCh. 12.5 - Prob. 12.7PPCh. 12.5 - Prob. 12.8PPCh. 12.5 - Prob. 12.9PPCh. 12.5 - Prob. 12.10PP
Ch. 12.6 - Prob. 12.11PPCh. 12.7 - Prob. 12.12PPCh. 12.7 - Prob. 12.13PPCh. 12.7 - Prob. 12.14PPCh. 12.7 - Prob. 12.15PPCh. 12 - Prob. 12.20HWCh. 12 - Derive a solution to the second readers-writers...Ch. 12 - Prob. 12.22HWCh. 12 - Prob. 12.23HWCh. 12 - Prob. 12.24HWCh. 12 - Prob. 12.25HWCh. 12 - Prob. 12.26HWCh. 12 - Some network programming texts suggest the...Ch. 12 - Prob. 12.28HWCh. 12 - Prob. 12.29HWCh. 12 - Prob. 12.30HWCh. 12 - Implement a version of the standard I/O fgets...Ch. 12 - Prob. 12.32HWCh. 12 - Prob. 12.33HWCh. 12 - Prob. 12.34HWCh. 12 - Prob. 12.35HWCh. 12 - Prob. 12.36HWCh. 12 - Prob. 12.37HWCh. 12 - Prob. 12.38HWCh. 12 - Prob. 12.39HW
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