This is a FreeRTOS header, not RTX.

davidskeck · web-flow · commit 5722d36f5452 · 2018-10-02T11:50:14.000-04:00
diff --git a/CMSIS/RTOS2/FreeRTOS/Include1/cmsis_os.h b/CMSIS/RTOS2/FreeRTOS/Include1/cmsis_os.h
@@ -21,7 +21,7 @@
  * $Revision:    V2.1.0
  *
  * Project:      CMSIS-RTOS API
- * Title:        cmsis_os.h RTX header file
+ * Title:        cmsis_os.h FreeRTOS header file
  *
  * Version 0.02
  *    Initial Proposal Phase

Original file line number	Diff line number	Diff line change
`@@ -21,7 +21,7 @@`
`21`	`21`	`* $Revision: V2.1.0`
`22`	`22`	`*`
`23`	`23`	`* Project: CMSIS-RTOS API`
`24`		`- * Title: cmsis_os.h RTX header file`
	`24`	`+ * Title: cmsis_os.h FreeRTOS header file`
`25`	`25`	`*`
`26`	`26`	`* Version 0.02`
`27`	`27`	`* Initial Proposal Phase`