Added overwrite output mode for things like live monitoring.

README.md

@@ -28,7 +28,7 @@ Access to the `/dev/i2c` device files, which means either:
 ## Optional features
 
 ### NVML support
-Add the make flag `USE_NVML=1` and the it will also display the main GPU temperature ("GPU1") as reported by the NVIDIA driver.  It will also display the performance cap/clock reason.  This requires NVML development files to be installed.
+Add the make flag `USE_NVML=1` and the it will also display the main GPU temperature ("GPU1") as reported by the NVIDIA driver.  It will also display the performance cap/clock reason.  This requires the NVIDIA management library (NVML) to be installed.
 
 ## Usage
 Note that when controlling fans directly through iCX3 they will fall offline from the Nvidia driver and show as 0 RPM until you return them to automatic mode.
@@ -46,6 +46,7 @@ Available options:
 --sensors    : Print sensor readings even if setting a fan speed
 --compact    : Print sensor reading in a compact one-line per card format
 --watch N    : Keep printing output every N seconds
+--overwrite  : Overwrite previously displayed info with --watch instead of continuously logging
 ```
 
 ### Examples:

evga-card.h

@@ -86,6 +86,7 @@
 struct card_info {
 	char *card_name;
 	char *pci_id;
+	unsigned short pci_device_id;
 	char *i2c_dev_path;
 	int i2c_fd;
 	int product_id;

evga-icx.c

@@ -25,7 +25,8 @@ static const char helpstring[] = "Available options:\n"
 								 "--reset      : Reset all fans to their default mode\n"
 								 "--sensors    : Print sensor readings even if setting a fan speed \n"
 								 "--compact    : Print sensor reading in a compact one-line per card format\n"
-								 "--watch N    : Keep printing output every N seconds\n";
+								 "--watch N    : Keep printing output every N seconds\n"
+								 "--overwrite  : Overwrite previously displayed info with --watch and --compact instead of continuously logging\n";
 								 
 void print_gpu_info(int gpu_num, struct card_info gpus[], int compact);
 
@@ -36,6 +37,7 @@ int main (int argc, char **argv)
 	int print_info = 0;
 	int compact = 0;
 	int gpu_num = -1;    /* Card to control */
+	int overwrite = 0;
 	unsigned int watch = 0;
 	char *fan_speed[ICX3_MAX_FANS] = {NULL}; 
 	
@@ -83,6 +85,8 @@ int main (int argc, char **argv)
 				printf(helpstring);
 				return -1;
 			}
+		} else if (strcmp(argv[i], "--overwrite") == 0) {
+			overwrite = 1;
 		} else {
 			printf(helpstring);
 			return 0;
@@ -98,6 +102,10 @@ int main (int argc, char **argv)
 		}
 	}
 	
+	/* Don't use overwrite mode unless set to compact (we can't tell how many lines the output will be per GPU) */
+	if (overwrite && !compact)
+		overwrite = 0;
+	
 	gpu_count = find_evga_gpu_i2cs(gpus, MAX_GPUS);
 
 	if (gpu_count == -1) {
@@ -131,20 +139,35 @@ int main (int argc, char **argv)
 	
 	/* NVML init */
 #ifdef USE_NVML
-	int nvml_ok = init_nvml();
+    init_nvml();
-	nvmlDevice_t* device[MAX_GPUS];
 #endif
 	
 	/* print sensor info */
 	if (print_info) {
 		do {
+			printf("\x1b[K");	/* Clear current console line (really just for overwrite mode) */
+			
 			if (gpu_num == -1) {
+				/* No GPU specified on command line, loop over all supported GPUs */
 				for (int i = 0; i < gpu_count; i++){
+					if (i > 0)
+						printf("\n");
 					print_gpu_info(i, &gpus[i], compact);
 				}		
 			} else if (gpu_num <= gpu_count - 1) {
 				print_gpu_info(gpu_num, &gpus[gpu_num], compact);
 			}
+
+			if (!overwrite)
+				printf("\n"); /* Print line break at the end for continuous output */
+			
+			if (overwrite && compact) {
+				printf("\x1b[1G");						/* Move cursor back to column 1 */
+				if (gpu_count > 1)
+					printf("\x1b[%dA", gpu_count-1);	/* Move cursor back up to the top of gpu list */
+			}
+			
+			fflush(stdout);
 			sleep(watch);
 		} while (watch > 0);
 	}
@@ -168,7 +191,6 @@ void print_gpu_info(int gpu_num, struct card_info *gpu, int compact) {
 #ifdef USE_NVML
 		print_nvml_clock_reason(1, gpu);
 #endif
-		printf("\n");
 	} else {
 		/* One line per GPU sensor */
 		printf("#%d: %s (%s) @ %s\n", gpu_num, gpu->card_name, gpu->i2c_dev_path, gpu->pci_id);
@@ -180,7 +202,6 @@ void print_gpu_info(int gpu_num, struct card_info *gpu, int compact) {
 #ifdef USE_NVML
 		print_nvml_clock_reason(0, gpu);
 #endif
-		printf("\n");
 	}
 	
 }

nvidia-sensors.c

@@ -2,14 +2,12 @@
 
 #include "nvidia-sensors.h"
 
-int init_nvml()
+void init_nvml()
 {
 	nvmlReturn_t result;
 	result = nvmlInit_v2();
-	if (result != NVML_SUCCESS) {
+	if (result != NVML_SUCCESS)
 		printf("Could not init NVML: %s\n", nvmlErrorString(result));
-		return 0;
-	}
 }
 
 void print_nvml_temp(int compact, struct card_info *card)

nvidia-sensors.h

@@ -21,7 +21,7 @@ static struct clock_reason clock_reason_names[] =
 	{nvmlClocksEventReasonDisplayClockSetting,			"DispClk",	"Display clock"}
 };
 
-int init_nvml();
+void init_nvml();
 void print_nvml_temp(int compact, struct card_info *card);
 void print_nvml_clock_reason(int compact, struct card_info *card);
 unsigned int get_nvml_temp(struct card_info *card);