#include <sys/select.h>
#include <sys/time.h>
#include <sys/types.h>
#include <unistd.h>
/* return value:
* END_OF_FILE: End of File
* More than 0: read bytes from stdin
* Less than 0: error
* 0 : nodata
*/
int get_stdin(int block, char *buf, int buflen)
{
/* man 2 select, for details */
struct timeval tv;
fd_set rfds;
int retval;
char *ret;
tv.tv_sec = TIME_OUT_S;
tv.tv_usec = TIME_OUT_US;
/* Watch stdin (fd 0) to see when it has input. */
FD_ZERO(&rfds);
FD_SET( STDIN, &rfds);
if(block)
retval = select( ( STDIN + 1), &rfds, NULL, NULL, &tv);
else
retval = select( ( STDIN + 1), &rfds, NULL, NULL, NULL);
/* Don't rely on the value of tv now! */
//} else if( FD_ISSET( STDIN, &rfds) ) {
if( retval > 0 ) {
bzero(buf, buflen);
/* read() retval:0 endoffile, retval:-1 error*/
/* gets() ignore the newline and ENDOFFILE */
ret = gets( buf );
if(ret == NULL)
return END_OF_FILE;
}
/* error: -1 , no data: 0, read bytes number */
return retval;
}