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Full Discussion: How to Run a Linux Command and Redirect its output to a socket in C
Top Forums Programming How to Run a Linux Command and Redirect its output to a socket in C Post 302258408 by Corona688 on Friday 14th of November 2008 01:03:22 PM
Old 11-14-2008
I think you can redirect the output to a stream socket if you fork and exec rather than using popen. This is because the redirection has to happen before you run the program, not after.

Code:
{
  pid_t pid=fork();
  int st;

  if(pid < 0)
  {
    perror("Couldn't fork");
  }
  else if(pid == 0) /* child code, run in a seperate process */
  {
    dup2(sock, 1); /* Duplicate socket's FD over FD #1, aka stdout */
    dup2(sock, 0); /* Duplicate socket's FD over FD #0, aka stdin */
    close(sock); /* Only closes the child's copy.  And the stdin/stdout copies remain. */
    execlp("/bin/echo", "HEY GUYS ALJ AF MY FACE IS A ROTTORN BANANA");
    /* Code below will never happen unless exec fails */
    perror("Couldn't exec");
    exit(1);
  }
  else
  {
    close(sock); /* Parent doesn't need socket anymore */
    waitpid(pid, &st, 0); /* Wait for child to finish */
  }
}

 

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LEARN ABOUT DEBIAN

lspcmcia

PCCARDCTL(8)						      System Manager's Manual						      PCCARDCTL(8)

NAME

       pccardctl - PCMCIA card control utility
       lspcmcia - display extended PCMCIA debugging information

SYNOPSIS

       pccardctl [-V] [-v ...] command [socket]
       lspcmcia [-V] [-v ...] [socket]

DESCRIPTION

       pccardctl is used to monitor and control the state of PCMCIA sockets.  If a socket number is specified, the command will be applied to just
       one socket; otherwise, all sockets will be affected.

       If pccardctl is executed by root, all commands are available.  If it is executed by an unpriviledged user, only the informational  commands
       are accessible.

       lspcmcia is an alias for pccardctl ls, provided for convenience.

COMMANDS

       status
	   Display the current socket status flags.

       config
	   Display  the socket configuration, including power settings, interrupt and I/O window settings, and configuration registers.  --not yet
	   implemented

       ident
	   Display card identification information, including product identification strings, manufacturer ID codes, and function ID  codes.   Not
	   yet implemented for cardbus cards. Use lspci instead.

       info
	   Much  like  the  ident  command, but its output is formatted as a series of Bourne-stype shell variable definitions for use in scripts.
	   Not yet implemented for cardbus cards.

       ls  Display extended debugging information about the PCMCIA sockets and devices present in the system.

       suspend
	   Shut down and then disable power for a socket.

       resume
	   Restore power to a socket, and re-configure for use.

       eject
	   Notify all client drivers that this card will be ejected, then cut power to the socket.

       insert
	   Notify all client drivers that this card has just been inserted.

OPTIONS

       -V     Show version information and exit.

       -v     Increase the verbosity of the ls command.  Giving this option twice increases verbosity further.

AUTHOR

       Daniel Ritz - daniel.ritz@gmx.ch
       based upon the original cardctl man page by
       David Hinds - dahinds@users.sourceforge.net

pcmciautils							    2005/10/22							      PCCARDCTL(8)
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