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HomeBackend DevelopmentPHP Tutorial一个字符指针定位的有关问题,请问上各位

一个字符指针定位的问题,请教下各位。

<?php											<br />	$handle=fopen ("many.txt","r");				<br />		//首先读取第1行,读取完毕后,指针在最后一行<br />	$buffer=fgets($handle,1024);					//读取第1行内容<br />	echo $buffer ."<br>";							<br />	//接着将指针向后移动5个字节<br />	echo ftell($handle)."<br>";<br />	fseek($handle,6,seek_cup);						//指针向后移动6个字节<br />		//接着读取一行<br />	$buffer=fgets($handle,1024);					//接着读取第1行内容<br />	echo $buffer . "<br>";						<br />		//将指针返回到到文件开始,重新读取第1行,因为是绝对位置为0<br />	fseek($handle,0);								<br />		//读取一行数据,因为指针回到文件开始,所以会读取第1行数据<br />	$buffer=fgets($handle,1024);					//再读取第1行文字<br />	echo $buffer ."<br>";							//输出读取内容<br />	fclose ($handle);								//关闭打开文件<br />?>						


程序中第一次按行读取文件之后,文件指针应该是在第一行的末尾。如果再往后移动指针应该指针是在第二行了,为什么程序结果显示的是文件指针移动到了第一行的第7个位置,相当于从头开始移动指针的。但是函数参数明明是从当前的位置往后移动6个位置啊。

这里附上many.txt 第二行我随便打的,因为程序结果只用到了第一行。
姓名:张三 年龄15 性别:男<br />llllllllllllllllllllllllllll

buffer fseek
------解决方案--------------------
SEEK_CUR
而且应该大写
------解决方案--------------------
是 SEEK_CUR 
而不是 seek_cup

seek_cup 在屏蔽错误的情况下只能是 0
也就是 SEEK_SET 了
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