这里我以mysql查询日志为源文件输入，直接显示到网页中查看。



<?php$file='mysqld-slow.log';$fp=fopen($file,"r");$line=5000;$pos=-2;$t="";$data="";while($line>0){while($t!="\n"){$flag=fseek($fp,$pos,SEEK_END);if(fseek($fp,$pos,SEEK_END)==-1){rewind($fp);$t="\n";$line=0;}else{$t=fgetc($fp);$pos--;}}$t="";$line--;}while(!feof($fp)){$data.=fgets($fp);$data.='<br/>';}fclose($fp);echo$data?>


<?php$file='/path/to/file';$fp=fopen($file,"r");$line=2000;$pos=-2;$t="";$data="";while($line>0){while($t!="\n"){$flag=fseek($fp,$pos,SEEK_END);if(fseek($fp,$pos,SEEK_END)==-1){rewind($fp);$t="\n";$line=0;}else{$t=fgetc($fp);$pos--;}}$t="";$line--;}while(!feof($fp)){$data.=fgets($fp);$data.='<br/>';}fclose($fp);echo$data?>