Here is an example:
//Arb wave data
unsigned short waveBuffer[16]={0x0000,0x2000,0x4000,0x6000,0x8000,0xA000,0xC000,0xE000,0xFFFF,0xE000,0xC000,0xA000,0x8000,0x6000,0x4000,0x2000};
//Define Arb segment
strcpy(cmd_str,"TRAC:DEF 1,16\n");
viWrite(InstrSession,(unsigned char *)cmd_str,strlen(cmd_str),0);
//Arb wave header
strcpy(cmd_str,"TRAC:DATA#232");
viWrite(InstrSession,(unsigned char *)cmd_str,strlen(cmd_str),0);
//Write arb wave viWrite(InstrSession,(unsigned char *)waveBuffer,32,0);