kdb151: Example of how to retrieve status of the CTS modem signal in QNX4

Title: Example of how to retrieve status of the CTS modem signal in QNX4
Keywords: CTS, QNX4, qnx_ioctl
Date: May 29, 1997
KDB: KDB-151
Revision: 0.01
Author: Support
Distribution: External

#include        
#include        
#include        
#include        
#include        

/* Function to look at the CTS signal   */
/* Look in sys/qioctl.h for definitions */

void    main( int argc, char *argv[] ){

	FILE    *fpSerialr;
	unsigned long oldbits;
	unsigned long maskme[2]= { 0, 0 };


	if( argc < 1 ){
		printf( "USE: ctsme deviceName\n" );
		exit( -1 );
	}

	fpSerialr = fopen( argv[1], "r" );
	if( fpSerialr == NULL ){
		printf( "Error opening device %s for input\n", argv[1] );
		exit( -1 );
	}
	setbuf( fpSerialr, NULL );
	printf("\n\n");
	while( 1 )
		{
		qnx_ioctl( fileno( fpSerialr ), QCTL_DEV_CTL, maskme, 8,
				 &oldbits, 4);
		if ( oldbits & 0x00100000  ) printf("CTS is high\r");
				else printf("CTS is low \r");
		delay (100);
		}
}

End of KDB-151

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