如何使用Perl使批处理文件像简单的grep一样工作?
我已经知道了这个问题的明显答案:"只需下载<在此处插入喜欢的Windows grep或者类似grep的工具>"。但是,我在一个本地IT员工严格控制的环境中工作,以允许我们在计算机上拥有什么。可以这么说:我可以在Windows XP上访问Perl。这是我想到的一个快速的Perl脚本,它可以满足我的要求,但是我还没有弄清楚如何设置批处理文件,这样我就可以将命令输出通过管道传递到其中,或者传递文件(或者文件列表) ?)作为" grep表达式"之后的参数:
perl -n -e "print $_ if (m![expression]!);" [filename]
我如何编写可以执行类似操作的批处理脚本,例如:
dir | grep.bat mypattern grep.bat mypattern myfile.txt
编辑:即使我标记了另一个"答案",我也想对Ray Hayes的答案表示敬意,因为这实际上是执行此操作的" Windows方式",即使另一个答案在技术上更接近我想要的。
解决方案
grep的大多数功能已在计算机上的Windows应用程序FindStr.exe中提供,该应用程序是所有Windows 2000,XP和Vista计算机的一部分!它提供RegExpr等。
比批处理文件要容易得多,后者又会调用Perl!
c:\>FindStr /?
Searches for strings in files.
FINDSTR [/B] [/E] [/L] [/R] [/S] [/I] [/X] [/V] [/N] [/M] [/O] [/P] [/F:file]
[/C:string] [/G:file] [/D:dir list] [/A:color attributes] [/OFF[LINE]]
strings [[drive:][path]filename[ ...]]
/B Matches pattern if at the beginning of a line.
/E Matches pattern if at the end of a line.
/L Uses search strings literally.
/R Uses search strings as regular expressions.
/S Searches for matching files in the current directory and all
subdirectories.
/I Specifies that the search is not to be case-sensitive.
/X Prints lines that match exactly.
/V Prints only lines that do not contain a match.
/N Prints the line number before each line that matches.
/M Prints only the filename if a file contains a match.
/O Prints character offset before each matching line.
/P Skip files with non-printable characters.
/OFF[LINE] Do not skip files with offline attribute set.
/A:attr Specifies color attribute with two hex digits. See "color /?"
/F:file Reads file list from the specified file(/ stands for console).
/C:string Uses specified string as a literal search string.
/G:file Gets search strings from the specified file(/ stands for console).
/D:dir Search a semicolon delimited list of directories
strings Text to be searched for.
[drive:][path]filename
Specifies a file or files to search.
Use spaces to separate multiple search strings unless the argument is prefixed
with /C. For example, 'FINDSTR "hello there" x.y' searches for "hello" or
"there" in file x.y. 'FINDSTR /C:"hello there" x.y' searches for
"hello there" in file x.y.
Regular expression quick reference:
. Wildcard: any character
* Repeat: zero or more occurances of previous character or class
^ Line position: beginning of line
$ Line position: end of line
[class] Character class: any one character in set
[^class] Inverse class: any one character not in set
[x-y] Range: any characters within the specified range
\x Escape: literal use of metacharacter x
\<xyz Word position: beginning of word
xyz\> Word position: end of word
我们需要执行以下操作:
@echo off perl -x -S script.pl %1
"%1"将参数传递给Perl脚本。将其另存为.bat文件,一切顺利。
我前一段时间写了这个:
@rem = '--*-Perl-*--
@echo off
perl -x -S %0 %*
goto endofperl
@rem -- BEGIN PERL -- ';
#!d:/Perl/bin/perl.exe -w
#line 10
use strict;
#use Test::Setup;
use Getopt::Long;
Getopt::Long::Configure ("bundling");
my $ignore_case = 0;
my $number_line = 0;
my $invert_results = 0;
my $verbose = 0;
my $result = GetOptions(
'i|ignore_case' => $ignore_case,
'n|number' => $number_line,
'v|invert' => $invert_results,
'verbose' => $verbose,
);
my $regex = shift;
if ( $ignore_case ) {
$regex = "(?i:$regex)";
}
$regex = qr/$regex/;
print "$regex=$regex\n";
if ( $verbose ) {
print "Verbose: Ignoring case.\n" if $ignore_case;
print "Verbose: Printing file name and line number.\n" if $number_line;
print "Verbose: Inverting result set.\n" if $invert_results;
print "\n";
}
@ARGV = map { glob "$_" } @ARGV;
while ( <> ) {
my $matches = m/$regex/;
next unless $matches ^ $invert_results;
print "$ARGV\:$.:" if $number_line;
print;
}
__END__
:endofperl
我同意Axeman和Hayes先生关于为工作使用更好的工具的意见。也就是说,我们可以在批处理文件中尝试类似的操作,以对文件通配符表达式运行自定义脚本:
@echo off
for /f "usebackq delims==" %%f in (`dir /w /b %2`) do (
perl -n -e "print $_ if (m!%1!);" "%%f"
REM or something like: myperlscript.pl %1 "%%f"
)
这样,我们可以执行" grep mypattern myfile.txt"," grep mypattern。"," grep mypattern * .doc"等操作。
下载并安装ack。它是grep的替代品,并且由于Perl的魔术双模式.BAT / Perl脚本魔术,它将在命令行上为我们工作。
首先,将其变成一个真实的脚本,而不是单行代码:
use strict; use warnings; my $pattern = shift or die "Usage:pl2bat mygrep.pl<pattern> [files|-]\n"; while (<>) { print if /$pattern/ }
然后使用pl2bat将其转换为批处理文件:
##代码##这将创建" mygrep.bat"。
有关完全用Perl编写的功能齐全的grep(以及许多其他Unix应用程序),请参见Perl Power Tools项目。
如果我们只能运行Perl,虽然Perl Power Tools很好,但我通常更喜欢GnuWin32工具集。他们不需要安装。 (我们不需要管理特权,只需一个目录即可写入。)

