build: check runtime link file

c/c.go

@@ -97,15 +97,6 @@ func Qsort(base Pointer, count, elem uintptr, compar func(a, b Pointer) Int)
 
 // -----------------------------------------------------------------------------
 
-//go:linkname Stdin stdin
-var Stdin FilePtr
-
-//go:linkname Stdout stdout
-var Stdout FilePtr
-
-//go:linkname Stderr stderr
-var Stderr FilePtr
-
 //go:linkname Printf C.printf
 func Printf(format *Char, __llgo_va_list ...any) Int
 

c/c_default.go

@@ -0,0 +1,15 @@
+//go:build !linux
+// +build !linux
+
+package c
+
+import _ "unsafe"
+
+//go:linkname Stdin __stdinp
+var Stdin FilePtr
+
+//go:linkname Stdout __stdoutp
+var Stdout FilePtr
+
+//go:linkname Stderr __stderrp
+var Stderr FilePtr

c/c_linux.go

@@ -0,0 +1,15 @@
+//go:build linux
+// +build linux
+
+package c
+
+import _ "unsafe"
+
+//go:linkname Stdin stdin
+var Stdin FilePtr
+
+//go:linkname Stdout stdout
+var Stdout FilePtr
+
+//go:linkname Stderr stderr
+var Stderr FilePtr