接问一句 如何 读取 0x00-0x8f ？
我先 binmode 再 read 貌似不好使？
>
> On 8月8日, 下午7时24分, Anthony WU <
anthonywu...@gmail.com> wrote:> 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 <
p3r1w...@gmail.com>
> > To: PerlChina Mongers 讨论组 <
perlchina@googlegroups.com>
> > 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 <
anthonywu...@gmail.com> 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 <
p3r1w...@gmail.com>
> > >> To: PerlChina Mongers 讨论组 <
perlchina@googlegroups.com>
> > >> 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 <
anthonywu...@gmail.com> 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 <
p3r1w...@gmail.com>
> > >>>> To: PerlChina Mongers 讨论组 <
perlchina@googlegroups.com>
> > >>>> 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 <
cnhack...@gmail.com> wrote:
>
> > >>>>>> 能举例说明你要做的事情么？
>
> > >>>>>> 2009/8/7 perlw01f <
p3r1w...@gmail.com>
>
> > >>>>>>> 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
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