perl脚本将指定目录下的所有文件内容中ABC替换成qwe，BBHB替换成bdsf，JHI替换成jifdjs。

可以使用 Perl 的正则表达式和文件操作函数来实现这个需求。可以按如下步骤进行操作：

1. 打开指定目录，列出目录下所有文件。

opendir(DIR, "/path/to/directory") or die "Can't open directory: $!\n";
my @files = readdir(DIR);
closedir(DIR);

2. 遍历每个文件，读取文件内容，并进行替换操作。

foreach my $file (@files) {
    next if ($file =~ /^\./);  # 跳过隐藏文件
    open(FILE, "/path/to/directory/$file") or die "Can't open file: $!\n";
    my @lines = <FILE>;
    close(FILE);
    foreach my $line (@lines) {
        $line =~ s/ABC/qwe/g;    # 替换 ABC
        $line =~ s/BBHB/bdsf/g;  # 替换 BBHB
        $line =~ s/JHI/jifdjs/g; # 替换 JHI
    }
    open(FILE, ">/path/to/directory/$file") or die "Can't open file: $!\n";
    print FILE @lines;
    close(FILE);
}

3. 关闭文件和目录。

closedir(DIR);

完整代码如下：

opendir(DIR, "/path/to/directory") or die "Can't open directory: $!\n";
my @files = readdir(DIR);
closedir(DIR);

foreach my $file (@files) {
    next if ($file =~ /^\./);  # 跳过隐藏文件
    open(FILE, "/path/to/directory/$file") or die "Can't open file: $!\n";
    my @lines = <FILE>;
    close(FILE);
    foreach my $line (@lines) {
        $line =~ s/ABC/qwe/g;    # 替换 ABC
        $line =~ s/BBHB/bdsf/g;  # 替换 BBHB
        $line =~ s/JHI/jifdjs/g; # 替换 JHI
    }
    open(FILE, ">/path/to/directory/$file") or die "Can't open file: $!\n";
    print FILE @lines;
    close(FILE);
}