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Full Discussion: Question about NULL Character & fgets()
Top Forums Programming Question about NULL Character & fgets() Post 302253964 by f.ben.isaac on Monday 3rd of November 2008 07:49:56 AM
Old 11-03-2008
Lightbulb Question about NULL Character & fgets()
Assume client send the message " Hello ", i get output such as

Sent mesg: hello
Bytes Sent to Client: 6


Code:
bytes_received = recv(clientSockD, data, MAX_DATA, 0);
if(bytes_received)
{
                        send(clientSockD, data, bytes_received, 0);
                        data[bytes_received] = '\0';
                        printf("Sent mesg: %s", data);
                        cout<<"Bytes Sent to Client: "<<bytes_received<<endl;
}

clients send that data as follows:

Code:
cout<<"you: ";
fgets(clientInput, MAX_DATA, stdin); 
send(sockfd, clientInput, strlen(clientInput), 0);

Why?

bytes_received should be 5, not 6 ..... Any idea?

**************************************************************

Lets say we have:

Code:
cout<<"Enter a port: ";
cin>>portNum;

fgets(clientInput, MAX_DATA, stdin);

Does fgets() takes a "\0" from the previous input, as you know cin leaves \0 there? getline() does...
Last edited by f.ben.isaac; 11-03-2008 at 09:02 AM..
 

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LEARN ABOUT XFREE86

mesg

MESG(1)                                                            User Commands                                                           MESG(1)

NAME

       mesg - display (or do not display) messages from other users

SYNOPSIS

       mesg [option] [n|y]

DESCRIPTION

       The mesg utility is invoked by a user to control write access others have to the terminal device associated with standard error output.  If
       write access is allowed, then programs such as talk(1) and write(1) may display messages on the terminal.

       Traditionally, write access is allowed by default.  However, as users become more conscious of various security risks, there is a trend  to
       remove write access by default, at least for the primary login shell.  To make sure your ttys are set the way you want them to be set, mesg
       should be executed in your login scripts.

ARGUMENTS

       n      Disallow messages.

       y      Allow messages to be displayed.

       If no arguments are given, mesg shows the current message status on standard error output.

OPTIONS

       -v, --verbose
              Explain what is being done.

       -V, --version
              Display version information and exit.

       -h, --help
              Display help text and exit.

EXIT STATUS

       The mesg utility exits with one of the following values:

            0     Messages are allowed.

            1     Messages are not allowed.

           >1     An error has occurred.

FILES

       /dev/[pt]ty[pq]?

SEE ALSO

       login(1), talk(1), write(1), wall(1), xterm(1)

HISTORY

       A mesg command appeared in Version 6 AT&T UNIX.

AVAILABILITY

       The mesg command is part of the util-linux package and is available from https://www.kernel.org/pub/linux/utils/util-linux/.

util-linux                                                           July 2014                                                             MESG(1)
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