void ctrrobot()
{
if(readposition()==1)//co du lieu moi
{
if(cmdCtrlRobot ==8)
{
speed(100,100);
LED_L_ON;
}
else
{
speed(0,0);
LED_L_OFF;
}
}
}
int main(int argc, char **argv)
{
/* pipe to parent, pipe to child */
int p_prnt[2], p_chld[2];
/* default filename to read, source code of this program */
char *filename = "FILE1";
/* filehandle of file we are reading */
FILE *file;
/* process 'id', just a string of parent or child */
char *id;
/* pid used when seeing the fork result */
int pid;
/* pipe used in this process, assigned after fork */
int mypipe[2];
/* position of file, read from other partner */
off_t pos;
/* stat info, so we don't fseek past the end */
struct stat finfo;
/* all using a separate file if a name is given */
if(argc > 1)
{
filename = argv[1];
}
/* init the pipes */
if(pipe(p_prnt) || pipe(p_chld))
{
perror("pipe");
exit(1);
}
/* open the file */
if((file = fopen(filename, "r")) == NULL)
{
fprintf(stderr, "Failed to open '%s': %s\n",
filename, strerror(errno));
exit(1);
}
/* get the stat/size of the file */
if(fstat(fileno(file), &finfo))
{
perror("fstat");
exit(1);
}
/* fork and assign 'id' and 'mypipe' */
if((pid = fork()) < 0)
{
perror("fork");
exit(1);
}
else if(pid == 0)
{
id = "CHLD";
mypipe[0] = p_chld[0];
mypipe[1] = p_prnt[1];
/*
* the child should wait until the parent reads the first line
* and then position itself for the loop to begin with the second line
*/
pos = readposition(mypipe[0]);
fseek(file, pos, SEEK_SET);
}
else
{
id = "PRNT";
mypipe[0] = p_prnt[0];
mypipe[1] = p_chld[1];
}
/*
* main loop to
* read the line
* write the position to the other partner
* wait for the position from the other partner
* (it will read the next line in the mean-time)
* seek to the new position
*/
while(pos < finfo.st_size)
{
/* read */
readline(getpid(), file);
/* send pos */
writeposition(ftell(file), mypipe[1]);
/* get next */
pos = readposition(mypipe[0]);
/* seek */
fseek(file, pos, SEEK_SET);
}
/* get other side to close down */
writeposition(ftell(file), mypipe[1]);
/* clean up and exit */
close(mypipe[0]);
close(mypipe[1]);
fclose(file);
return(0);
}
