继续翻译

`MAKE_RESTARTS'     This variable is set only if this instance of `make' has restarted     (*note How Makefiles Are Remade: Remaking Makefiles.): it will     contain the number of times this instance has restarted.  Note     this is not the same as recursion (counted by the `MAKELEVEL'     variable).  You should not set, modify, or export this variable.`.RECIPEPREFIX'     The first character of the value of this variable is used as the     character make assumes is introducing a recipe line.  If the     variable is empty (as it is by default) that character is the     standard tab character.  For example, this is a valid makefile:          .RECIPEPREFIX = >          all:          > @echo Hello, world     The value of `.RECIPEPREFIX' can be changed multiple times; once     set it stays in effect for all rules parsed until it is modified.`.VARIABLES'     Expands to a list of the _names_ of all global variables defined     so far.  This includes variables which have empty values, as well     as built-in variables (*note Variables Used by Implicit Rules:     Implicit Variables.), but does not include any variables which are     only defined in a target-specific context.  Note that any value     you assign to this variable will be ignored; it will always return     its special value.

`MAKE_RESTARTS'

只有当 make 的实例重新启动后才会被设置(*note How Makefiles Are Remade: Remaking Makefiles.): 它会包含此实例重新启动的次数。请注意这个和递归(recursion)(由MAKELEVEL来计数)不同。你无法设定，更改或者导出此变量。

`.RECIPEPREFIX'这个变量的第一个字符被用作引入一个片段行。如果此变量的值为空(缺省值)，那么这个引入片段行的字符将是标准tab键。例如下面是一个有效的makefile。

.RECIPEPREFIX = >

all:

> @echo Hello, world

 `.RECIPEPREFIX' 的值可以被改变很多次; 一旦被设置就开始对所有规则有效，直到被再次改变为止。

`.VARIABLES'

扩展为一个所有全局变量的列表。其中包括拥有空值的，也包口内建的变量(*note Variables Used by Implicit Rules: Implicit Variables.)，但是不包括那些仅仅在目的特定的上下文中定义的变量。请注意任何你所设的值会被忽略，它总是返回其特殊值。

后文待续