Perl：用于登录特定文件的库

我正在为我的资料创建一个库，以便在其中记录特定文件上的错误。不幸的是，如果我只启动库的一个实例，它就可以工作，但如果我启动多个实例，它就不能工作

这种情况下的结果是，输出全部记录在最后一个文件中，而不是像我预期的一半

这是main.pl

eval 'exec /usr/bin/perl -I `pwd` -S $0 ${1+"$@"}'
if 0;

use strict;
use MyLibrary;

my ($rc, $test_2, $test_1);

# The output is not going into this file
exit $test_1 if (($test_1 = MyLibrary->new("/tmp", "test_1")) !~ "HASH");

# It is going all into this file
exit $test_2 if (($test_2 = MyLibrary->new("/tmp", "test_2")) !~ "HASH");

exit $rc if ( $rc = $test_1->test() );
exit $rc if ( $rc = $test_2->test() );

这是MyLibrary.pm

package MyLibrary;

use strict;
use Symbol;
use vars qw($VERSION @ISA @EXPORT %default);

@EXPORT = qw(
);
$VERSION = '1.00';

require 5.000;

%default;

my $fh;

sub new
{
   my $rc;
   my ($proto, $log_dir, $log_file) = @_;

   my $class = ref($proto) || $proto;

   my $self = { %default };

   bless($self, $class);

   $fh = gensym;
   ($self->{'log_dir'}, $self->{'log_file'}) = ($log_dir, $log_file);

   return $rc if ( $rc = $self->open_log_file() );

   return $self;
}

sub destroy
{
   my $rc;
   my $self = shift;

   return $rc if ( $rc = $self->close_log_file() );
}

sub open_log_file
{
   my $self = shift;

   open $fh, ">>$self->{'log_dir'}/$self->{'log_file'}" or die "cannot open file $self->{'log_dir'}/$self->{'log_file'}";

   return 0;
}

sub close_log_file
{
   my $self = shift;

   close($fh) or die "cannot close $self->{'log_dir'}/$self->{'log_file'}";

   return 0;
}

sub test
{
    my $self = shift;

    print $fh "[$self->{'log_file'}]\n";

   return 0;
}
1;

还有一件事。。。在本例中，我使用

$fh

作为全局变量，同时我希望将此变量作为

%default

哈希的一部分。但是，如果我尝试将所有

$fh

发生的事件替换为

$self->{'fh'}

，则会出现以下错误：

String found where operator expected at MyLibrary.pm line 75, near "} "[$self->{'log_file'}]\n""
    (Missing operator before  "[$self->{'log_file'}]\n"?)
syntax error at MyLibrary.pm line 75, near "} "[$self->{'log_file'}]\n""

在这种情况下，第75行将如下所示：

sub test
{
    my $self = shift;

Row 75 =>>>    print $self->{'fh'} "[$self->{'log_file'}]\n";

    return 0;
}

而相应审查的完整库为：

package MyLibrary;

use strict;
use Symbol;
use vars qw($VERSION @ISA @EXPORT %default);

@EXPORT = qw(
);
$VERSION = '1.00';

require 5.000;

%default;

sub new
{
   my $rc;
   my ($proto, $log_dir, $log_file) = @_;

   my $class = ref($proto) || $proto;

   my $self = { %default };

   bless($self, $class);

   $self->{'fh'} = gensym;
   ($self->{'log_dir'}, $self->{'log_file'}) = ($log_dir, $log_file);

   return $rc if ( $rc = $self->open_log_file() );

   return $self;
}

sub destroy
{
   my $rc;
   my $self = shift;

   return $rc if ( $rc = $self->close_log_file() );
}

sub open_log_file
{
   my $self = shift;

   open $self->{'fh'}, ">>$self->{'log_dir'}/$self->{'log_file'}" or die "cannot open file $self->{'log_dir'}/$self->{'log_file'}";

   return 0;
}

sub close_log_file
{
   my $self = shift;

   close($self->{'fh'}) or die "cannot close $self->{'log_dir'}/$self->{'log_file'}";

   return 0;
}

sub test
{
    my $self = shift;

    print $self->{'fh'} "[$self->{'log_file'}]\n";

   return 0;
}
1;

---

根据经验，似乎

print

语句中的文件句柄不能是任意表达式。这实际上只是对代码的一个小修改，但为了编译

MyLibrary.pm

，我替换了：

print $self->{'fh'} "[$self->{'log_file'}]\n";

与：

还有其他一些小的调整，但这段代码对我很有用：

MyLibrary.pm 我不相信

使用5.000非常适合你。找到仍在运行的Perl4.x的机会非常渺茫。现在，任何早于Perl5.8的东西都早已过时（或者，如果不是的话，它应该是）

上面没有显示的代码中有许多小的改进

testcase.pl
第n次样本运行
看起来我在添加
print\u data
函数之前运行了一次以前版本的
testcase.pl
，在添加
print\u data
函数之后运行了四次

$ perl -I$PWD testcase.pl
OK 1
OK 2
OK 3
OK 4
OK 5
Finished
$ cat /tmp/test_1
[test_1]
[test_1]
Extra information
[test_1]
Extra information
[test_1]
Extra information
[test_1]
Extra information
$ cat /tmp/test_2
[test_2]
[test_2]
Missing syncopation
[test_2]
Missing syncopation
[test_2]
Missing syncopation
[test_2]
Missing syncopation
$

欢迎来到堆栈溢出。请尽快阅读这一页。你是否考虑过使用它的众多相关模块？如果是这样，你为什么不使用它？如果没有，请这样做。不幸的是，我不能使用外部库满足客户的需求，这就是为什么我需要了解如何自己制作。嗯；运气不好，不得不不断地重新发明轮子。请尽量确保它们是圆的。我感到有点惊讶的是，在Perl本身的相同条款下获得许可的软件存在明显的问题。如果您可以使用Perl，为什么不使用其他软件呢？然而，律师并不擅长将逻辑应用于此类情况。
package MyLibrary;

use warnings;
use strict;
use vars qw($VERSION @ISA @EXPORT %default);

@EXPORT = qw();
$VERSION = '1.00';

require 5.000;

sub new
{
   my ($proto, $log_dir, $log_file) = @_;
   my $class = ref($proto) || $proto;
   my $self = { %default };

   bless($self, $class);

   $self->{'log_dir'} = $log_dir;
   $self->{'log_file'} = $log_file;
   $self->open_log_file();

   return $self;
}

sub destroy
{
   my $rc;
   my $self = shift;

   return $rc if ( $rc = $self->close_log_file() );
}

sub open_log_file
{
   my $self = shift;
   my $log_file = "$self->{log_dir}/$self->{log_file}";
   open $self->{'fh'}, ">>", $log_file or die "cannot open file $log_file";
   return;
}

sub close_log_file
{
   my $self = shift;

   close($self->{'fh'}) or die "cannot close $self->{'log_dir'}/$self->{'log_file'}";
   return;
}

sub print_data
{
    my $self = shift;
    my $fh = $self->{fh};
    print $fh @_, "\n";
}

sub test
{
    my $self = shift;
    my $fh = $self->{'fh'};
    print $fh "[$self->{'log_file'}]\n";

   return 0;
}
1;

#!/usr/bin/env perl
use warnings;
use strict;
use MyLibrary;

my ($rc, $test_2, $test_1);

my $counter = 0;
sub counter
{
    printf"OK %d\n", ++$counter;
}

counter;

# The output is not going into this file
exit $test_1 if (($test_1 = MyLibrary->new("/tmp", "test_1")) !~ "HASH");
counter;

# It is going all into this file
exit $test_2 if (($test_2 = MyLibrary->new("/tmp", "test_2")) !~ "HASH");
counter;

exit $rc if ( $rc = $test_1->test() );
counter;
exit $rc if ( $rc = $test_2->test() );
counter;

$test_1->print_data("Extra information");
$test_2->print_data("Missing syncopation");
print "Finished\n";

$ perl -I$PWD testcase.pl
OK 1
OK 2
OK 3
OK 4
OK 5
Finished
$ cat /tmp/test_1
[test_1]
[test_1]
Extra information
[test_1]
Extra information
[test_1]
Extra information
[test_1]
Extra information
$ cat /tmp/test_2
[test_2]
[test_2]
Missing syncopation
[test_2]
Missing syncopation
[test_2]
Missing syncopation
[test_2]
Missing syncopation
$