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  • 取关键字下第2行

    open( A, "<", "abc" ) || die "$!
    ";
      @count=();
      while (<A>){
          $num++;
          if ($_ =~ /error/i)
             {$b=$num;
              print "$b is $b
    ";
              open( B, "<", "abc" ) || die "$!
    ";
              while (<B>){
              print "$. is $.
    ";
              if ($. == $b + 1){print "$_ is $_
    "};
                 }
              #close B;
               };
         };
    	 
    Vsftp:/root# cat -n abc
         1	1
         2	2
         3	3aA
         4	313
         5	error
         6	4234
         7	12341
         8	ERROR
         9	666
        10	sdaad
        11	error
        12	313
        13	3131
    	 
    Vsftp:/root# perl a2.pl 
    $b is 5
    $. is 1
    $. is 2
    $. is 3
    $. is 4
    $. is 5
    $. is 6
    $_ is 4234
    
    $. is 7
    $. is 8
    $. is 9
    $. is 10
    $. is 11
    $. is 12
    $. is 13
    $b is 8
    $. is 14
    $. is 15
    $. is 16
    $. is 17
    $. is 18
    $. is 19
    $. is 20
    $. is 21
    $. is 22
    $. is 23
    $. is 24
    $. is 25
    $. is 26
    $b is 11
    $. is 27
    $. is 28
    $. is 29
    $. is 30
    $. is 31
    $. is 32
    $. is 33
    $. is 34
    $. is 35
    $. is 36
    $. is 37
    $. is 38
    $. is 39
    
    文件句柄不关闭,会读完后继续读
    
    关闭文件句柄后
    
    
    Vsftp:/root# cat abc
    1
    2
    3aA
    313
    error
    4234
    12341
    ERROR
    666
    sdaad
    error
    313
    3131
    Vsftp:/root# perl a2.pl 
    $_ is 12341
    
    $_ is sdaad
    
    $_ is 3131
    
    Vsftp:/root# cat a2.pl 
    open( A, "<", "abc" ) || die "$!
    ";
      @count=();
      while (<A>){
          $num++;
          if ($_ =~ /error/i)
             {$b=$num;
              open( B, "<", "abc" ) || die "$!
    ";
              while (<B>){
              if ($. == $b + 2){print "$_ is $_
    ";close B;last;};
                 }
               };
         };

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  • 原文地址:https://www.cnblogs.com/hzcya1995/p/13349969.html
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