golang syscall_linux 代码
文件路径：/src/runtime/internal/syscall/syscall_linux.go
/ Copyright 2022 The Go Authors. All rights reserved.
/ Use of this source code is governed by a BSD-style
/ license that can be found in the LICENSE file.
/ Package syscall provides the syscall primitives required for the runtime.
package syscall
import (
_ "unsafe" / for go:linkname
)
/ TODO(https://go.dev/issue/51087): This package is incomplete and currently
/ only contains very minimal support for Linux.
/ Syscall6 calls system call number 'num' with arguments a1-6.
func Syscall6(num, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, errno uintptr)
/ syscall_RawSyscall6 is a push linkname to export Syscall6 as
/ syscall.RawSyscall6.
/
/ /go:uintptrkeepalive because the uintptr argument may be converted pointers
/ that need to be kept alive in the caller (this is implied for Syscall6 since
/ it has no body).
/
/ /go:nosplit because stack copying does not account for uintptrkeepalive, so
/ the stack must not grow. Stack copying cannot blindly assume that all
/ uintptr arguments are pointers, because some values may look like pointers,
/ but not really be pointers, and adjusting their value would break the call.
/
/ This is a separate wrapper because we can't export one function as two
/ names. The assembly implementations name themselves Syscall6 would not be
/ affected by a linkname.
/
/go:uintptrkeepalive
/go:nosplit
/go:linkname syscall_RawSyscall6 syscall.RawSyscall6
func syscall_RawSyscall6(num, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, errno uintptr) {
return Syscall6(num, a1, a2, a3, a4, a5, a6)
}