Re: replacing high order ascii chars using sed

From: Stephane CHAZELAS (stephane_chazelas@yahoo.fr)
Date: 04/15/03

  • Next message: Bill Marcum: "Re: replacing high order ascii chars using sed" 
    From: Stephane CHAZELAS <stephane_chazelas@yahoo.fr>
Date: 15 Apr 2003 09:44:01 GMT

    Josh Buedel wrote:
    > I'm trying to write a sed script that will replace certain control
    > characters and high order ascii chars with a printable character. I'm using
    > cygwin on a win2000 machine, from the windows command (cmd.exe) line.
    >
    > I have a couple of questions:
    >
    > 1. This command line
    > sed "s/[[:cntrl:]]/X/g" b2.bin
    > and this command line
    > sed "s/[\x00-\x19\x7F]/X/g" b2.bin
    > do not produce the same results. Why is this?
    >
    > 2. The byte size of the output was 12 bytes bigger than b2.bin's original
    > size of 851, for both expressions. Why is this? I'm replacing a single
    > character with a single character (I think).

    It seems to me that MS Windows has two types of file: binary and
    text, sed is a text utility, I don't know how it handles binary
    files, it may do some conversions (on NL or CR chars). I don't
    know wether CR is in cntrl on Windows or not.

    >
    > 3. What would the correct regular expression/command line be? I want to
    > replace all characters 0x7F and up with an 'X'.

    Use "tr" instead of sed (but pay attention to CR and NL chars). 

    -- 
Stéphane
  • Next message: Bill Marcum: "Re: replacing high order ascii chars using sed"

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