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 replace(1)                                                       replace(1)

      replace - Replace strings in text or binary files in a sane fashion

      replace [-?] [-A] [-b] [-c startcol] [-d tmpdir] [-e] [-f] [-h] [-i]
      [-L] [-l linenum] [-m maxreplines] [-n] [-P] [-p] [-r|-R] [-s] [-T] [-
      t maxtimes] [-u backupsuffix] [-v] [-w] [-x suffix[-x...]] [-z] old_str
      new_str [-a old_str new_str] [filename [filename...]]

      replace performs (by default) a case-insensitive search for the "word"
      old_str in each text line and replaces it with new_str, which is (by
      default) case-adjusted to match the case of the particular occurrence
      of old_str in the original line.  A "word" is defined to be a string
      that is preceded AND followed by a non-alphanumeric character (start
      and end of lines count as such a character) in the original text line.
      The original versions of any modified files are (by default) saved
      with a ".cln" extension.

      If no filenames are specified, then standard input and output are used
      for the replacements unless -r or -R is additionally specified (which
      will cause the current directory to be recursed for files instead).
      If "filenames" are specified with -r or -R, then they can either be
      files or the names of directories that will be recursed for files.  If
      possible, modified files retain their ownership, group and

      The following options are recognised:

           -?   Display a syntax usage message.

           -A   By default, replace uses the first 256 bytes of each file
                specified to automatically determine if the file is text or
                binary. By specifying this option, this auto-detection is
                turned off and replace assumes that all supplied files are
                text files. It is recommended that you avoid this option
                unless absolutely necessary due to the high risk of
                corruption of binary files that may be accidentally
                specified. Because of its dangerous nature, -A is now a
                deprecated option and may change its behaviour or be removed
                in a future release.

           -a old_str new_str
                Allows extra replacement strings to be specified in strict
                left-to-right order.  The maximum number of replacement
                pairs is 255. This is equivalent to sed's multiple -e
                parameters of course, so please note that the whole line is
                modified by the first replacement pair before it is
                rescanned for subsequent pairs. If -b or -h has been

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 replace(1)                                                       replace(1)

                specified or the auto-detect code indicates the file is a
                binary, the binary input data is read in 16K chunks and the
                binary replacement pairs are applied in turn to each chunk
                (chunk-straddling is catered for of course).

           -b   Turns off file type auto-detection and forces replace to
                assume that all supplied files are binary files (i.e. the
                inverse of the -A option).  The replacement string (new_str)
                must be less than or equal in length to the original string
                (old_str) and will not be zero-terminated unless -z is also
                supplied or padded with spaces unless -P or -p is used.
                Note that all binary replacements do not check if old_str is
                a "word" i.e. the -s option is enabled.  Neither old_str nor
                new_str can be zero length (i.e. "") when -b is used.

           Note that -b turns on initial checks about the suitability of the
           old and new strings for use in binary replacements (namely that
           old_str must not be zero length and new_str must be less than or
           equal to the length of old_str).  Without the -b (or -h) option,
           such unsuitable strings are allowed, but will be silently ignored
           if the auto-detect code finds a binary file and attempts string
           replacements on it.

           -c startcol
                Starts the string replacement from column 'linenum' onwards
                rather than the first column onwards. Ignored if -b or -h is
                also specified or if the auto-detect code indicates the file
                is a binary.

           -d tempdir
                Specifies the temporary directory used for storing modified
                files. If the parameter is not supplied, then the
                environmental variable TMPDIR is read and used instead. If
                TMPDIR is also not set, then /tmp will be used.

           -e   Make the search case-sensitive. new_str exactly replaces
                old_str with no case-adjustment to new_str.

           -f   Forces the update of files without any backup (which
                typically has a .cln suffix).

           -h   The original and replacement strings are normally ASCII
                strings, but -h switches their format to be hex strings of
                binary data. It also activates case-sensitive binary
                replacement mode (i.e. it switches on the -b and -e
                options). If you wanted, for example, to replace all
                occurrences of the byte 0 with the byte 255 instead, you'd
                specify "-h 0 ff".

           -i   When specified once, the user will be interactively prompted
                whether they want the next file to have all of the

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 replace(1)                                                       replace(1)

                appropriate strings replaced.  When specified twice ("-i
                -i"), the prompting switches to asking about every single
                string replacement in each file (the appropriate unmodified
                line is displayed to aid the user). As a safety precaution,
                verbose mode is also switched on when -i is specified (to
                the level of the number of -i's stated). Note that the input
                is read from /dev/tty to avoid clashing with standard input
                and any prompts are, of course, sent to standard error.

           -L   Follows any soft-link specified on the command line to its
                linked-to destination before performing any replacements.
                If a soft-link eventually points to a directory and the -r
                or -R option has been specified, then that directory will be
                recursed (but any soft-links inside that directory will not
                be followed to avoid jumping out of the directory tree). If
                -L isn't supplied, soft-links specified on the command line
                will be skipped.

           -l linenum
                Starts the string replacement from line 'linenum' onwards
                rather than the first line onwards. Ignored if -b or -h is
                also specified or if the file is auto-detected as a binary.

           -m maxreplines
                Specifies the maximum number of lines that should have their
                strings replaced in a file. The default value is infinity.
                Ignored if -b or -h is also specified or if the file is
                auto-detected as a binary.

           -n   Displays what strings would be replaced without actually
                replacing them.  It also, by necessity, switches on summary
                verbose mode (specify -nn to switch on all replacements
                verbose mode).

           -P   Pre-pads new_str with leading spaces if it is shorter than

           -p   Pads new_str with trailing spaces if it is shorter than

           -r or -R
                Recurses the filesystem from the current directory downwards
                (if no "filenames" are specified), replacing strings in
                every file found.  Soft-links within the directory tree are
                ignored to avoid the recursion jumping out of that tree.
                The recursion can look for particular file suffixes only by
                the use of one or more -x parameters. If "filenames" are
                specified along with -r or -R, then they can either be files
                or the names of directories to recurse down for files.  Note
                that files ending in the backup suffix (typically .cln) will
                be skipped during the recursion.

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 replace(1)                                                       replace(1)

           -s   Relaxes the condition that old_str has to match a "word"
                i.e. it replaces old_str even if it is a substring of a
                "word" or if it contains only non-alphanumeric characters.

           -T   Modified files retain the timestamps of the original
                unmodified files if this option is specified. By default,
                modified files have their timestamp set to the time the file
                was modified (i.e. now).

           -t maxtimes
                States the maximum number of times a string can be replaced
                in any single line of a file. The default value is infinity.
                If -b or -h is also specified or the file is auto-detected
                as a binary, the maxtimes value applies to the whole binary
                input file.

           -u backupsuffix
                Changes the backup suffix of the unmodified file from the
                default of .cln to the specified backupsuffix value.

           -v   Increments (switches on) verbose mode. If specified once,
                only a brief per-file summary is reported to stderr of the
                files that had replacements performed on them.  If specified
                twice (i.e. -vv), all individual replacements are
                additionally reported to stderr and an overall summary is
                also displayed. If -v isn't specified at all (and -i or -n
                aren't used), then only warnings and errors are displayed to
                stderr (in other words, replace operates silently by default
                if there are no problems).

           -w   Recursively replaces strings in all Web-related source files
                in the current directory tree. Equivalent to "-r -x .html -x
                .htm -x .asp -x .js -x .css -x .xml -x .xhtml -x .shtml -x
                .jsp -x .php -x .php3 -x .php4 -x .pl".

           -x suffix
                Specifies the suffix of the files to be case-insensitively
                matched when -r is used.  Multiple -x parameters can be
                utilised with the appropriate "or" meaning as you'd expect.
                The maximum number of -x parameters is 255.

           -z   Zero-terminate any binary replacement string (new_str)
                specified, which is useful if you are replacing a zero-
                terminated string (e.g. a pathname) with a smaller string in
                an executable. If this option is used, -b must also be
                supplied (note that using -h or -p will cause -z to be
                ignored) and also new_str must be shorter than old_str in
                order to cater for the zero terminator.

      If replace has no non-fatal errors, it will return 0, otherwise it

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 replace(1)                                                       replace(1)

      returns 1. Fatal errors can include bad command line options or
      parameters, failure to allocate memory for replacement buffers,
      failure to read from the terminal when expecting user input and
      exiting replace via the "q" option when being prompted for input
      during "replace -i".

      To make an executable use /usr/lib/libc.1 instead of /usr/lib/libc.2
      (note that this is "risky" and may lead to run-time problems for the
      executable, but it's one way to try to run an HP-UX 11.00 binary on
      HP-UX 10.20 !):

      replace -bv /usr/lib/libc.2 /usr/lib/libc.1 filename

      To make a file one long line (i.e. replace all line feeds with

      replace -h a 20 filename

      To recursively add the attribute bgcolor="#ffffff" to all <body> tags
      (regardless of case) in all Web-related source documents in the
      current directory tree downwards (but retaining the original case of
      the <body> tag):

      replace -fswv "<body" "<body bgcolor=\"#ffffff\""

      If the old or new string or the filenames you are specifying contain a
      space or any special shell character (e.g. brackets, pipe, backquote
      and so on), use single or double quotes to surround the whole string.
      If you want to remove a string from a file, specify "" as the new
      string to replace the old one.  If the old or new string begins with a
      minus ("-"), you will have to stop command line argument parsing with
      -- (e.g. replace -sev -- -old new...).

      Replacing strings in binary executables, object files or libraries can
      lead to permanent corruption of said files if you perform the
      replacements in a haphazard manner. You are strongly advised to keep a
      backup copy of any such binary files you intend to replace strings in.

      Do not use the -A option (which is now officially deprecated) unless
      you are completely convinced that all files specified are text files.
      You risk severe corruption of any binaries specified otherwise.


      Richard K. Lloyd    <>

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