我把 seek 第二 及第三個參數寫反了，刪除是不能的，但你可以通過 先讀 0x00-0x8f 跳到0xb0再讀到EOF並把所取得的BYTES寫到新檔案
-------- Original Message -------- Subject: [PerlChina] Re: 16进制文件操作 From: perlw01f <[email protected]> To: PerlChina Mongers 讨论组 <[email protected]> Date: 8/8/2009 10:42 > 谢谢 > perldoc -f seek的结论貌似跟这个不一样 ？ > > seek FILEHANDLE,POSITION,WHENCE > Sets FILEHANDLE's position, just like the "fseek" call of > "stdio". FILEHANDLE may be an expression whose value gives > the > name of the filehandle. The values for WHENCE are 0 to set > the > new position *in bytes* to POSITION, 1 to set it to the > current > position plus POSITION, and 2 to set it to EOF plus POSITION > (typically negative). For WHENCE you may use the constants > "SEEK_SET", "SEEK_CUR", and "SEEK_END" (start of the file, > current position, end of the file) from the Fcntl module. > Returns 1 upon success, 0 otherwise. > > Note the *in bytes*: even if the filehandle has been set to > operate on characters (for example by using the ":utf8" open > layer), tell() will return byte offsets, not character > offsets > (because implementing that would render seek() and tell() > rather > slow). > > If you want to position file for "sysread" or "syswrite", > don't > use "seek"--buffering makes its effect on the file's system > position unpredictable and non-portable. Use "sysseek" > instead. > > Due to the rules and rigors of ANSI C, on some systems you > have > to do a seek whenever you switch between reading and > writing. > Amongst other things, this may have the effect of calling > stdio's clearerr(3). A WHENCE of 1 ("SEEK_CUR") is useful > for > not moving the file position: > > seek(TEST,0,1); > > This is also useful for applications emulating "tail -f". > Once > you hit EOF on your read, and then sleep for a while, you > might > have to stick in a seek() to reset things. The "seek" > doesn't > change the current position, but it *does* clear the end-of- > file > condition on the handle, so that the next "<FILE>" makes > Perl > try again to read something. We hope. > > If that doesn't work (some IO implementations are > particularly > cantankerous), then you may need something more like this: > > for (;;) { > for ($curpos = tell(FILE); $_ = <FILE>; > $curpos = tell(FILE)) { > # search for some stuff and put it into files > } > sleep($for_a_while); > seek(FILE, $curpos, 0); > } > > > > 另外，您的code 我尝试了一下 > seek ($fp, 0, 0x80); > print $fp "\x0"; > 实际的效果是 00000000h这一行 第1和2字节变成了0 没有偏移？ > 我自己尝试 > seek ($fp, 16*8, 0x00); > print $fp "\x0"; > 可以达到目的 > > 另外 我想请教 如何删除掉一部分内容呢 比如 0x90-0xb0 > 谢谢 > On 8月8日, 上午12时48分, Anthony WU <[email protected]> wrote: > >> 以你所說的操作大約是 >> open (my $fp, '+<', 'x.dat'); >> binmode ($fp); >> seek ($fp, 0, 0x80); >> print $fp "\x0"; >> seek ($fp, 0, 0x82); >> print $fp "\x0"; >> seek ($fp, 0, 0x84); >> print $fp "\x0"; >> seek ($fp, 0, 0x86); >> print $fp "\x8B"; >> seek ($fp, 0, 0x87); >> print $fp "\x8B"; >> seek ($fp, 0, 0x88); >> print $fp "\x0A"; >> seek ($fp, 0, 0x89); >> print $fp "\x0A"; >> .... >> .... >> .... >> close ($fp); >> >> >> >> -------- Original Message -------- >> Subject: [PerlChina] Re: 16进制文件操作 >> From: perlw01f <[email protected]> >> To: PerlChina Mongers 讨论组 <[email protected]> >> Date: 7/8/2009 21:16 >> >>> 都是在确定的位置 >>> >>> 如 00000080h 这一栏 第1 3 5 字节换为0 78换为8B 9 10 换为0A 还有一些其他的 >>> >>> On 8月7日, 下午9时04分, Anthony WU <[email protected]> wrote: >>> >>>> 你的字節是定位修改的嗎？有什麼規律的？ >>>> >>>> -------- Original Message -------- >>>> Subject: [PerlChina] Re: 16进制文件操作 >>>> From: perlw01f <[email protected]> >>>> To: PerlChina Mongers 讨论组 <[email protected]> >>>> Date: 7/8/2009 20:56 >>>> >>>>> 我有一个文件 x.dat，由x.rar.gz压缩而成 但是其中某些字节做了修改处理 现在的文件名是 a.dat >>>>> 现在 我想逆行操作，即 >>>>> 先将a.date rename成x.rar.gz 然后利用ue修改某些字节 之后才能解压缩成x.date >>>>> >>>>> 由于文件数量较多 且ue 16进制 修改也不是很方便 >>>>> 所以想 用 perl实现 >>>>> 谢谢 >>>>> >>>>> On 8月7日, 下午5时17分, cnhack TNT <[email protected]> wrote: >>>>> >>>>>> 能举例说明你要做的事情么？ >>>>>> >>>>>> 2009/8/7 perlw01f <[email protected]> >>>>>> >>>>>>> perl中 有没有类似ultredit中那种直接转换成16进制进行操作的方法或者module >>>>>>> >>>>>>> unpack是不是太费事了 >>>>>>> >>>> -- >>>> Best Regards, >>>> Anthony WU >>>> >> -- >> Best Regards, >> Anthony WU >> > > > > -- Best Regards, Anthony WU --~--~---------~--~----~------------~-------~--~----~ 您收到此信息是由于您订阅了 Google 论坛“PerlChina Mongers 讨论组”论坛。 要在此论坛发帖，请发电子邮件到 [email protected] 要退订此论坛，请发邮件至 [email protected] 更多选项，请通过 http://groups.google.com/group/perlchina?hl=zh-CN 访问该论坛 -~----------~----~----~----~------~----~------~--~---
