auto add a carriage return in front of a line feed, how to delete this auto character.

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

#the list is consist of the hex numbers
#my @list = (0x0040,0x0041,...,0x000a,0x0065...);
#I translate the hex to the decimal using hex()
#now @list = (64,65,...,10,101,...);
then I using the follow code.

my $outputstring = pack("n*", @list);
print TARGET_FILE $outputstring;
[download]

but each time it will add a carriage return character(0x000d) in front of the character(0x000a, line feed)
any method for delete this 0x000d?
I use the binmode

binmode TARGET_FILE;
my $outputstring = pack("n*", @list);
print TARGET_FILE $outputstring;
[download]

it works well for big-endian
but when comes to little-endian

binmode TARGET_FILE;
my $outputstring = pack("v*", @list);
print TARGET_FILE $outputstring;
[download]

it is still auto add a carriage return in front of a line feed, any ideas?

Comment on auto add a carriage return in front of a line feed, how to delete this auto character. Select or Download Code

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Re: auto add a carriage return in front of a line feed, how to delete this auto character. by Util (Priest) on May 21, 2008 at 03:12 UTC
Either: `binmode TARGET_FILE;` [download] or: `open TARGET_FILE, '>:raw', $filename;` [download] See also: binmode	[reply] [d/l] [select]
Re^2: auto add a carriage return in front of a line feed, how to delete this auto character. by xhsoldier (Initiate) on May 21, 2008 at 03:34 UTC
All methods are works. that is great. thanks a lot, all.	[reply]
Re: auto add a carriage return in front of a line feed, how to delete this auto character. by pc88mxer (Vicar) on May 21, 2008 at 03:22 UTC
I gather you are running ActiveState perl on a Windows box. A PerlIO layer is responsible for converting the newline into a cr-lf sequence. As others have suggested, you can read up on I/O layers via `perldoc perlio`. To solve your problem, try one of these: `binmode STDOUT, ":unix"; binmode STDOUT, ":raw";` [download] To see what I/O layers are active for `STDOUT`, use: `print "@{[PerlIO::get_layers(STDOUT)]}\n";` [download] My ActiveState Win32 perl reports the layers `unix crlf` for `STDOUT`. On the same box, however, Cygwin perl reports the single layer `stdio`.	[reply] [d/l] [select]
Re: auto add a carriage return in front of a line feed, how to delete this auto character. by Anonymous Monk on May 21, 2008 at 03:10 UTC
perldoc -f binmode	[reply]
Re^2: auto add a carriage return in front of a line feed, how to delete this auto character. by xhsoldier (Initiate) on May 21, 2008 at 04:52 UTC
I use the binmode `binmode TARGET_FILE; my $outputstring = pack("n", @list); print TARGET_FILE $outputstring;` [download] it works well for big-endian but when comes to little-endian `binmode TARGET_FILE; my $outputstring = pack("v", @list); print TARGET_FILE $outputstring;` [download] it is still auto add a carriage return in front of a line feed, any ideas?	[reply] [d/l] [select]
Re^3: auto add a carriage return in front of a line feed, how to delete this auto character. by ikegami (Patriarch) on May 21, 2008 at 06:18 UTC
but when comes to little-endian [...] it is still auto add a carriage return in front of a line feed No it doesn't. Either it adds CRs before LFs or it doesn't. It doesn't know or care how the string was constructed. Something else changed. `open TARGET_FILE, '>', 'foo' or die; binmode TARGET_FILE; my @list = 10; my $outputstring = pack("v*", @list); print TARGET_FILE $outputstring;` [download] `>perl script.pl >debug script.out -rcx CX 0002 : -d100 l2 0B02:0100 0A 00 .. -q` [download] PS — Why are you using a global variable (as in `TARGET_FILE`) for your file handle instead of a lexical? The former hasn't been required for 8 years.	[reply] [d/l] [select]