Application.mk and main.c files: Change builtin's entry point from main to xxx_main by macro expansion. This change make the entry point fully compliant with POSIX/ANSI standard.

examples/modbusmaster/Kconfig

@@ -4,7 +4,7 @@
 #
 
 config EXAMPLES_MODBUSMASTER
-	bool "Modbus Master example"
+	tristate "Modbus Master example"
 	default n
 	---help---
 		Enable the Modbus Master example
@@ -14,7 +14,6 @@ if EXAMPLES_MODBUSMASTER
 config EXAMPLES_MODBUSMASTER_PROGNAME
 	string "Program name"
 	default "modbusmaster"
-	depends on BUILD_KERNEL
 	---help---
 		This is the name of the program that will be used when the NSH ELF
 		program is installed.

examples/modbusmaster/Makefile

@@ -37,18 +37,13 @@ include $(TOPDIR)/Make.defs
 
 # Modbus Master built-in application info
 
-CONFIG_EXAMPLES_MODBUSMASTER_PRIORITY ?= SCHED_PRIORITY_DEFAULT
-CONFIG_EXAMPLES_MODBUSMASTER_STACKSIZE ?= 2048
-
-APPNAME = mbmaster
+PROGNAME = $(CONFIG_EXAMPLES_MODBUSMASTER_PROGNAME)
 PRIORITY = $(CONFIG_EXAMPLES_MODBUSMASTER_PRIORITY)
 STACKSIZE = $(CONFIG_EXAMPLES_MODBUSMASTER_STACKSIZE)
+MODULE = $(CONFIG_EXAMPLES_MODBUSMASTER)
 
 # Modbus Master Example
 
 MAINSRC = mbmaster_main.c
 
-CONFIG_EXAMPLES_MODBUSMASTER_PROGNAME ?= mbmaster$(EXEEXT)
-PROGNAME = $(CONFIG_EXAMPLES_MODBUSMASTER_PROGNAME)
-
 include $(APPDIR)/Application.mk

examples/modbusmaster/mbmaster_main.c

@@ -261,11 +261,7 @@ eMBErrorCode eMBMasterRegHoldingCB(FAR uint8_t *buffer,
  * Name: main/mbmaster_main
  ****************************************************************************/
 
-#ifdef CONFIG_BUILD_KERNEL
 int main(int argc, FAR char *argv[])
-#else
-int mbmaster_main(int argc, FAR char *argv[])
-#endif
 {
   eMBMasterReqErrCode mberr;
   int reqcounter = 0;