Question

我有一个这样的文件：

01 00 01 14 c0 00 01 10 01 00 00 16 00 00 00 64
00 00 00 65 00 00 01 07 40 00 00 22 68 61 6c 2e
6f 70 65 6e 65 74 2e 63 6f 6d 3b 30 30 30 30 30
30 30 30 32 3b 30 00 00 00 00 01 08 40 00 00 1e
68 61 6c 2e 6f 70 65 6e 65 74 2d 74 65 6c 65 63
6f 6d 2e 6c 61 6e 00 00 00 00 01 28 40 00 00 21
72 65 61 6c 6d 31 2e 6f 70 65 6e 65 74 2d 74 65
6c 65 63 6f 6d 2e 6c 61 6e 00 00 00 00 00 01 25
40 00 00 1e 68 61 6c 2e 6f 70 65 6e 65 74 2d 74
65 6c 65 63 6f 6d 2e 6c 61 6e 00 00 00 00 01 1b
40 00 00 20 72 65 61 6c 6d 2e 6f 70 65 6e 65 74
2d 74 65 6c 65 63 6f 6d 2e 6c 61 6e 00 00 01 02
40 00 00 0c 01 00 00 16 00 00 01 a0 40 00 00 0c
00 00 00 01 00 00 01 9f 40 00 00 0c 00 00 00 00
00 00 01 16 40 00 00 0c 00 00 00 00 00 00 01 bb
40 00 00 28 00 00 01 c2 40 00 00 0c 00 00 00 00
00 00 01 bc 40 00 00 13 31 39 37 37 31 31 31 32
32 33 31 00

我正在读取文件，然后查找某些八位字节并用标签替换它们：

while(<FH>){
    $line =~ s/(00 00 00 64)/<incr4>    /g;
    $line =~ s/(00 00 00 65)/<incr4>    /g;
    $line =~ s/(30 30 30 30 30 32)/<incr6ascii:999999:0>/g;
    $line =~ s/(31 31 32 32 33 31)/<incr6ascii:999999:0>/g;
    print OUTPUT $line;
}

例如，00 00 00 64将替换为<incr4>标记。这工作正常，但它似乎不能再匹配多行。例如，模式31 31 32 32 33 31在多行上运行，而正则表达式似乎没有捕获它。我尝试使用/ m / s模式修饰符忽略新行，但它们也不匹配。我能想到的唯一方法就是使用以下方法将整个文件读成字符串：

undef $/;
my $whole_file = <FH>;
my $line = $whole_file;
$line =~ s/(00 00 00 64)/<incr4>    /g;
$line =~ s/(00 00 00 65)/<incr4>    /g;
$line =~ s/(30 30 30 30 30 32)/<incr6ascii:999999:0>/g;
$line =~ s/(31 31 32 32 33 31)/<incr6ascii:999999:0>/g;
print OUTPUT $line;

这样做，标签正确插入，但文件的结构发生了根本改变。它全部被抛弃在一条线上。我想保留文件的结构，因为它出现在这里。关于我如何做到这一点的任何想法？

/约翰

Answer 1

这里的技巧是匹配所有空格的类，如字符\s：

my $file = do {local (@ARGV, $/) = 'filename.txt'; <>}; # slurp file

my %tr = (  # setup a translation table
    '00 00 00 64'       => '<incr4>',
    '00 00 00 65'       => '<incr4>',
    '00 30 30 30 30 32' => '<incr6ascii:999999:0>',
    '31 31 32 32 33 31' => '<incr6ascii:999999:0>',
);

for (keys %tr) {
    my $re = join '\s+' => split;  # construct new regex

    $file =~ s{($re)}{
       $1 =~ /\n/ ? "\n$tr{$_}" : $tr{$_}  # if octets contained \n, add \n
    }ge  # match multiple times, execute the replacement block as perl code
}
print $file;

匹配多行perl正则表达式

1 个答案: