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go.sys/unix: just jump to syscall.Syscall etc.
Don't re-implement these functions. LGTM=rsc R=rsc CC=golang-codereviews https://golang.org/cl/124390043
This commit is contained in:
Rob Pike
+9
-162
@@ -2,185 +2,32 @@
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// TODO(rsc): Rewrite all nn(SP) references into name+(nn-8)(FP)
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// so that go vet can check that they are correct.
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#include "textflag.h"
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//
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// System calls for 386, Linux
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//
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// func Syscall(trap uintptr, a1, a2, a3 uintptr) (r1, r2, err uintptr);
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// Trap # in AX, args in BX CX DX SI DI, return in AX
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// Just jump to package syscall's implementation for all these functions.
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// The runtime may know about them.
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TEXT ·Syscall(SB),NOSPLIT,$0-28
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CALL runtime·entersyscall(SB)
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MOVL 4(SP), AX // syscall entry
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MOVL 8(SP), BX
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MOVL 12(SP), CX
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MOVL 16(SP), DX
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MOVL $0, SI
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MOVL $0, DI
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CALL *runtime·_vdso(SB)
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CMPL AX, $0xfffff001
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JLS ok
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MOVL $-1, 20(SP) // r1
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MOVL $0, 24(SP) // r2
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NEGL AX
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MOVL AX, 28(SP) // errno
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CALL runtime·exitsyscall(SB)
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RET
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ok:
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MOVL AX, 20(SP) // r1
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MOVL DX, 24(SP) // r2
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MOVL $0, 28(SP) // errno
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CALL runtime·exitsyscall(SB)
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RET
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JMP syscall·Syscall(SB)
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// func Syscall6(trap uintptr, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr);
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TEXT ·Syscall6(SB),NOSPLIT,$0-40
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CALL runtime·entersyscall(SB)
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MOVL 4(SP), AX // syscall entry
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MOVL 8(SP), BX
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MOVL 12(SP), CX
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MOVL 16(SP), DX
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MOVL 20(SP), SI
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MOVL 24(SP), DI
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MOVL 28(SP), BP
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CALL *runtime·_vdso(SB)
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CMPL AX, $0xfffff001
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JLS ok6
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MOVL $-1, 32(SP) // r1
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MOVL $0, 36(SP) // r2
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NEGL AX
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MOVL AX, 40(SP) // errno
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CALL runtime·exitsyscall(SB)
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RET
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ok6:
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MOVL AX, 32(SP) // r1
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MOVL DX, 36(SP) // r2
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MOVL $0, 40(SP) // errno
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CALL runtime·exitsyscall(SB)
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RET
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JMP syscall·Syscall6(SB)
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// func RawSyscall(trap uintptr, a1, a2, a3 uintptr) (r1, r2, err uintptr);
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TEXT ·RawSyscall(SB),NOSPLIT,$0-28
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MOVL 4(SP), AX // syscall entry
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MOVL 8(SP), BX
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MOVL 12(SP), CX
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MOVL 16(SP), DX
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MOVL $0, SI
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MOVL $0, DI
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CALL *runtime·_vdso(SB)
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CMPL AX, $0xfffff001
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JLS ok1
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MOVL $-1, 20(SP) // r1
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MOVL $0, 24(SP) // r2
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NEGL AX
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MOVL AX, 28(SP) // errno
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RET
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ok1:
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MOVL AX, 20(SP) // r1
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MOVL DX, 24(SP) // r2
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MOVL $0, 28(SP) // errno
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RET
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JMP syscall·RawSyscall(SB)
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// func RawSyscall6(trap uintptr, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr);
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TEXT ·RawSyscall6(SB),NOSPLIT,$0-40
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MOVL 4(SP), AX // syscall entry
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MOVL 8(SP), BX
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MOVL 12(SP), CX
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MOVL 16(SP), DX
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MOVL 20(SP), SI
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MOVL 24(SP), DI
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MOVL 28(SP), BP
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CALL *runtime·_vdso(SB)
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CMPL AX, $0xfffff001
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JLS ok2
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MOVL $-1, 32(SP) // r1
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MOVL $0, 36(SP) // r2
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NEGL AX
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MOVL AX, 40(SP) // errno
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RET
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ok2:
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MOVL AX, 32(SP) // r1
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MOVL DX, 36(SP) // r2
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MOVL $0, 40(SP) // errno
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RET
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JMP syscall·RawSyscall6(SB)
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#define SYS_SOCKETCALL 102 /* from zsysnum_linux_386.go */
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// func socketcall(call int, a0, a1, a2, a3, a4, a5 uintptr) (n int, errno int)
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// Kernel interface gets call sub-number and pointer to a0.
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TEXT ·socketcall(SB),NOSPLIT,$0-36
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CALL runtime·entersyscall(SB)
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MOVL $SYS_SOCKETCALL, AX // syscall entry
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MOVL 4(SP), BX // socket call number
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LEAL 8(SP), CX // pointer to call arguments
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MOVL $0, DX
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MOVL $0, SI
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MOVL $0, DI
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CALL *runtime·_vdso(SB)
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CMPL AX, $0xfffff001
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JLS oksock
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MOVL $-1, 32(SP) // n
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NEGL AX
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MOVL AX, 36(SP) // errno
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CALL runtime·exitsyscall(SB)
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RET
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oksock:
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MOVL AX, 32(SP) // n
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MOVL $0, 36(SP) // errno
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CALL runtime·exitsyscall(SB)
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RET
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JMP syscall·socketcall(SB)
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// func rawsocketcall(call int, a0, a1, a2, a3, a4, a5 uintptr) (n int, errno int)
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// Kernel interface gets call sub-number and pointer to a0.
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TEXT ·rawsocketcall(SB),NOSPLIT,$0-36
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MOVL $SYS_SOCKETCALL, AX // syscall entry
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MOVL 4(SP), BX // socket call number
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LEAL 8(SP), CX // pointer to call arguments
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MOVL $0, DX
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MOVL $0, SI
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MOVL $0, DI
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CALL *runtime·_vdso(SB)
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CMPL AX, $0xfffff001
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JLS oksock1
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MOVL $-1, 32(SP) // n
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NEGL AX
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MOVL AX, 36(SP) // errno
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RET
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oksock1:
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MOVL AX, 32(SP) // n
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MOVL $0, 36(SP) // errno
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RET
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JMP syscall·rawsocketcall(SB)
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#define SYS__LLSEEK 140 /* from zsysnum_linux_386.go */
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// func Seek(fd int, offset int64, whence int) (newoffset int64, errno int)
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// Implemented in assembly to avoid allocation when
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// taking the address of the return value newoffset.
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// Underlying system call is
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// llseek(int fd, int offhi, int offlo, int64 *result, int whence)
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TEXT ·seek(SB),NOSPLIT,$0-28
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CALL runtime·entersyscall(SB)
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MOVL $SYS__LLSEEK, AX // syscall entry
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MOVL 4(SP), BX // fd
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MOVL 12(SP), CX // offset-high
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MOVL 8(SP), DX // offset-low
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LEAL 20(SP), SI // result pointer
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MOVL 16(SP), DI // whence
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CALL *runtime·_vdso(SB)
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CMPL AX, $0xfffff001
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JLS okseek
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MOVL $-1, 20(SP) // newoffset low
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MOVL $-1, 24(SP) // newoffset high
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NEGL AX
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MOVL AX, 28(SP) // errno
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CALL runtime·exitsyscall(SB)
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RET
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okseek:
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// system call filled in newoffset already
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MOVL $0, 28(SP) // errno
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CALL runtime·exitsyscall(SB)
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RET
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JMP syscall·seek(SB)
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