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Old 09-14-2009, 08:35 PM   #1
hellgirl
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Registered: Sep 2009
Location: tulsa, ok
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open local file error when creating file descriptor


I have a error message when I ran my program

that I couldn't open my local file.


I have two files

first one is called client, second one is called server

I am using named pipes to sent a message from client to the other file called server

in client I
used mknod() to create the two named pipes, one for read, one for write

and created new thread in client

using fork() spawned a child process that executed the server file


both named pipes are opened

the client file got the message from the user

and sent it through the named pipes to the server file

when the server receives the message , it needs to verfify it is correct

in the server file, a local file descriptor is created to read and send
this verifing message when it is not correct




but I am getting an OPEN() error

when I tried to open this shared local array buff

and attach it to a file descriptor
where the message is kept

why do I get this error

in server file

int main()
{
/*both named pipes are open*/

rfd=open(IFIO1,0);
wfd=open(IFIO2,1);

server(rfd,wfd);
}

void server(int rfd, int wfd)
{
int localfile;
char buff[max];
char buff2[max];

n=read(rfd,buff,max);

if ((localfile = open(buff,0)) < 0) /*error line I have question*/
{


/* we got a open error */
/* now tell the IPC Client */

sprintf(buff2,"Filename %s Failed on Open Terminating", buff);

n=strlen(buff2);
buff2[n]='\0';


if(write(wfd, buff2, n) != n)
{

/* write error on the IPC descriptor */
 
Old 09-14-2009, 10:03 PM   #2
estabroo
Senior Member
 
Registered: Jun 2008
Distribution: debian, ubuntu, sidux
Posts: 1,092
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Rep: Reputation: 109Reputation: 109
before you do the sprintf you might want to perror("open failed") to find out what caused the open to fail
 
  


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