fuctions

join

​$(join <list1>,<list2>)

连接函数

把list2 中单词对应的添加到list1 的后面

若list1 的单词个数> list2 ，多出的list1  保持不变

若list2 的单词个数> list21，多出的list2 添加到list1 后面

foreach

​$(foreach <var>,<list>,<text>)

for循环函数

把list的单词逐一取出放在参数 var 里面，然后在执行text所包含的表达式

call

​$(call <function>,<param1>,<param2>,...)

call 调用其他的函数

param1 对应$(1) ,以此类推

origin

​$(origin var)

查询var变量的来源

有如下几种返回值

default，默认的

environment，环境变量

undefined，未定义的

file，makefile内定义的

command line

override，被override重新定义的

automatic，自动化变量

shell

​$(shell  pwd)

 可以与awk 和sed 使用

error

​$(error  <texts> )

makefile 控制函数，输出error 信息 

warning

​$(warning  <texts>)

makefile 控制函数，输出warning 信息

example 

list1 := 111 222 333
list2 := aaa bbb ccc ddd 
list :=  $(join $(list1),$(list2) ) ################################################
#### foreach var,list,text
####  loop in list ,and put evevy item in var and do  text 
################################################
for_data= item env monitor 
rst_for := $(foreach var,$(for_data),$(var).sv )################################################
#### common if 
#### when  condition return is not "" [strip xxx],call  'then_part' ,else call 'else part' 
#### $(if <condition>,<then patr>,<else part> ) 
#### $(if <condition>,<then patr>) 
rst_if = $(if name==ryz, name is ryz,name is not ryz)################################################
#### call function,param1,param2,param3,....
#### call others functions 
################################################
max=$(2) $(1).sv
rst_call:=$(call max,119,33)################################################
#### origin var 
#### tell var from 
#### if var not define ,return undefined
#### if define in makefine ,return file
#### if var is a default  ,return default 
#### if var is a environment and make not -e option ,return environment
#### if define in makefine ,return file
#### return command line 
#### return override 
#### return automatic 
################################################
var_file := llll
var_file:=$(origin $(var_file) )
var_undefined = $(origin $(var_no) )################################################
#### shell 
#### using awk and sed         
################################################rst_pwd := $(shell pwd)################################################
#### makefile control functions 
#### $(error text),quit now
#### $(warning text),only type text,not quit
################################################
warning_info := $(warning get a warning msg)
error_info =$(error  get an error)ifdef ERROR_MSG$(error_info)
endiferr:$(error_info)war:$(warning_info)all:@echo $(list)@echo $(rst_for)@echo $(rst_if)@echo $(rst_call)@echo $(var_file)@echo $(rst_pwd)