top cmd: Introduce non-standard --once option for test systems

1 files changed, 13 insertions, 2 deletions

diff --git a/src/systemcmds/top/top.c b/src/systemcmds/top/top.c
index 37e913040..ababbadf4 100644
--- a/src/systemcmds/top/top.c
+++ b/src/systemcmds/top/top.c
@@ -56,7 +56,7 @@
 /**
  * Start the top application.
  */
-__EXPORT int top_main(void);
+__EXPORT int top_main(int argc, char *argv[]);
 
 extern struct system_load_s system_load;
 
@@ -89,7 +89,7 @@ tstate_name(const tstate_t s)
 }
 
 int
-top_main(void)
+top_main(int argc, char *argv[])
 {
 	uint64_t total_user_time = 0;
 
@@ -107,6 +107,13 @@ top_main(void)
 
 	float interval_time_ms_inv = 0.f;
 
+	bool once = false;
+
+	if (argc > 1) {
+		/* non-standard once argument: Prints load once and exits */
+		once = !strcmp(argv[1], "--once");
+	}
+
 	/* clear screen */
 	printf("\033[2J");
 
@@ -252,6 +259,10 @@ top_main(void)
 
 		interval_start_time = new_time;
 
+		if (once) {
+			return OK;
+		}
+
 		/* Sleep 200 ms waiting for user input five times ~ 1s */
 		for (int k = 0; k < 5; k++) {
 			char c;