getenv.s

用于嵌入式Linux系统的标准C的库函数

; @(#)getenv.s	1.4 90/10/14 21:57:45, AMD
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; Copyright 1990 Advanced Micro Devices, Inc.
;
; This software is the property of Advanced Micro Devices, Inc  (AMD)  which
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; software provided this notice is not removed or altered.  All other rights
; are reserved by AMD.
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; getenv.s
;	char *value = getenv( const char *name );
;
	.file	"getenv.s"

	.include "sys/sysmac.h"

	.text
	.word	0x00030000	; Debugger tag word
	.global	_getenv
	.global	__getenv
_getenv:
__getenv:
	const tav,HIF_getenv @ asneq V_SYSCALL,gr1,gr1		; HIF service trap
	jmpti	tav, lr0	; If tav is true, were finished, return.
	const	tpc, _errno
	consth	tpc, _errno	; Otherwise,
	store	0, 0, tav, tpc	;   store error code in _errno,
	jmpi	lr0		;   then return
	const	v0, 0		;   with a value of 0 (NULL pointer).

	.end