Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question: 

Input file:
88,100,2287432,1,0,400,2287432,52,12, ^M
16,275,2287432,0,0041880118XF,,/ ^M
88,REMARK : STANDING INSTR FROM: 323-126065 ADT FLOAT XFER CREDIT ^M
16,469,207805,0,2348128762TC,,/ ^M
________________________________________________________________


I'm trying to get rid of space before ^M.where ^M is a special charact
+er (its one byte i.e ^M is one character)I'm using following code but
+ its not working.Any Suggestion please... Thanks.
_______________________________________________________________
#!/usr/bin/perl
open (diff, "<dave.00063");                                           
+     
open (out, ">SAPPDAY.00063.new");                                     
+     
$count=0;                                                             
+     
while (<diff>) {                                                      
+     
   if (/(^16|^88)/) {                                                 
+     
     chomp $_ ;                                                       
+    
     @words=split(/,/, $_)  ;                                         
+    
     $field_cnt=$#words ;                                             
+    
     #print "  Field count = $field_cnt\n" ;                          
+     
     $last_length=length($words[$field_cnt]) ;                        
+    
     #print "  Field length= $last_length\n" ;                        
+    
     $num1 =$last_length-1;                                           
+    
     $num2 =$num- 1;                                                  
+    
     #print " NUM 1 = [$num1]\n" ;                                    
+   
      if ( substr($words[$field_cnt], $num1, 1) eq " " ) {            
+     
       $part1 = substr($words[$field_cnt], 0, $num2 ) ;               
+     
       $part2 = substr($words[$field_cnt], $last_length, 1 ) ;        
+    
       $words[$field_cnt] = $part1 . $part2 ;                         
+    
       print "$words[field_cnt]\n"                                    
+    
      }                                                               
+     
      exit;                                                           
+     
   }                                                                  
+       
}

[download]

Replies are listed 'Best First'.
Re: substring function
by Fastolfe (Vicar) on Sep 29, 2000 at 20:04 UTC
    If you want clean output text, with proper newlines for your OS at the end of each line, instead of that weird dangling ^M (which tells me that perhaps the file isn't native to that OS, and/or was not properly transferred via ASCII when it was FTP'd?), a simple regular expression (or perhaps even something simpler like chomp or chop) might do the job for you: 
    s/\s*$/\n/s;        # assuming \s will catch your newline
s/\s*[\r\n]+$/\n/;  # otherwise, this should do it

    [download]
    Or, if you just want to use substr: 
    substr($_, -2, 2) = undef;   # deletes last 2 characters
substr($_, -3, 3) = "\n";    # if your string ends in a newline

    [download]
[reply]
[d/l]
[select]
      I do want to preserve that ^M character and also the new line character. Please give any suggestion how to use substring func.to do just that.
[reply]
        If you literally want to clear the 2nd character from the end (i.e. byte 49 of 50 bytes), you could do this with substr: 
        substr($string, -2, 1) = undef;

        [download]
        That should neatly cut that character out of the string. My instincts tell me you're doing something "the hard way", though. I really cannot see the value of having a binary ^M sitting out near the end of ASCII text file lines. I would only expect to see that with improperly transferred files between systems that use incompatible newlines. I don't quite understand what you're trying to accomplish, but my gut tells me you're going about this problem (whatever your true problem is) the wrong way.

        Good luck.

[reply]
[d/l]
Re: substring function
by ar0n (Priest) on Sep 29, 2000 at 19:17 UTC 
    Input file:
88,100,2287432,1,0,400,2287432,52,12, ^M
16,275,2287432,0,0041880118XF,,/ ^M
88,REMARK : STANDING INSTR FROM: 323-126065 ADT FLOAT XFER CREDIT ^M
16,469,207805,0,2348128762TC,,/ ^M

    [download]
    I'm trying to get rid of space before ^M, where ^M is a special character (it's one byte i.e ^M is one character) I'm using following code but its not working. Any suggestion please... Thanks. 
    open (diff, "SAPPDAY.00063.new");
$count = 0;
while () {
    if (/(^16|^88)/) {
        chomp $_;
        @words = split(/,/, $_);
        $field_cnt = $#words;

        # print "  Field count = $field_cnt\n";

        $last_length = length $words[$field_cnt];

        # print "  Field length= $last_length\n";

        $num1 = $last_length-1;
        $num2 = $num - 1;

        # print " NUM 1 = [$num1]\n";

        if ( substr($words[$field_cnt], $num1, 1) eq " " ) {
            $part1 = substr($words[$field_cnt], 0, $num2 );
            $part2 = substr($words[$field_cnt], $last_length, 1);
            $words[$field_cnt] = $part1 . $part2;
            print "$words[$field_cnt]\n";
        }
        exit;
    }
}

    [download]

    [ar0n, super-hero by night]

[reply]
[d/l]
[select]
      #!/usr/bin/perl -w

use strict;

open FILE, "SAPPDAY.00063.new" or die "Ack! Can't open: $!\n";

while(<FILE>) {
        if(/^(?:16|88)/) {
                s/\s+\r\n$/\r\n/g;
                print;       
        }
}

close FILE;

      [download]

      Get a book.

      update
      d'oh! see Fastolfe's post.

      [ar0n]

[reply]
[d/l]
Re: substring function
by cianoz (Friar) on Sep 29, 2000 at 18:32 UTC
    use the <code> tag when you post your code!
[reply]

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