Bad File descriptor error on strcat

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August 18th, 2004, 06:47 AM

lyn

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Bad File descriptor error on strcat

I need help trying to figure why this piece of code gives me a "Bad File descriptor error" everytime I try to run it and invoke fflush. This piece of code simple outputs a char string to the output stream.
What ends up happening instead is that when outputting the first character string to the channel CG_cdukeypad_CHA.Scrpad, its gives the bad file descriptor error, causing the char string not to output. When a second char string is received by the pointer and copied to the channel, the first character string appears on the output stream without the error message. When the third char string is received, the second char string appears on the output stream w/o the error msg, so on and so forth.

Quote:

CG_cdukeypad_CHA.Scrpad is a channel to the output stream.
cdukeypad->Scrpad points to the value that I want to pass to the output stream.

PHP Code:


		
			
if (strlen(cdukeypad->Scrpad) > 0){

  printf("Character received is %s.\n", cdukeypad->Scrpad);

    if (strlen(CG_cdukeypad_CHA.Scrpad) < 25){

        strcat(CG_cdukeypad_CHA.Scrpad, cdukeypad->Scrpad);

    }

    if (fflush(NULL) == EOF){

      VP_INFO(("Error writing text to Scratchpad.\n"));

      VP_INFO(("Error is %s\n", strerror(errno)));

    }

  }

Thanks in advance for any help...

August 18th, 2004, 07:38 AM

DaWei_M

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fflush takes a FILE* as an argument, not a file descriptor. NULL isn't a valid FILE*, thus has no reference to a valid file descriptor.

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August 18th, 2004, 07:43 AM

mitakeet

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fflush(NULL) flushes all open file descriptors. http://www.rt.com/man/fflush.3.html

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August 18th, 2004, 08:40 AM

lyn