by That script converts from relative to absolute. He wants to convert from
absolute to relative.
> > Can anyone provide some hints on how to convert absolute symbolic
> > links to relative?
> I read (and reread and reread :) your previous post here on your
> dtksh script, and although I can say I don't have any clear idea
> of what you are trying to accomplish -- which is not to say that
> it hasn't been acceptably described -- then perhaps a function to
> turn relative pathnames into absolute pathname, with optional
> resolution of symbolic links and/or path lookup.... Does this help
> you in your problem?
> =Brian
> P.S. BTW, why are you using sed(1) instead of builtin pattern substitution
> in ksh93?! (${var//pattern/string}). Why are you using expr(1)
> instead of builtin arithmetic?! (heck, floating-point even!) Why
> awk(1) when you can use ${#var} and word-separation parsing?! The
> ratio of execution can be as high as 10000 (not a typo) times
> faster!
> #! /bin/echo error: only source
> #*TAG:42576 4:Jan 9 1973:0755:resolvepath:
> # Copyright: (c) 2000
> # Description: resolve and canonicize full pathname of arguments
> # Name: resolvepath
> # Requires:
> # See-also: File-PathConvert-0.4.tar (perl)
> # Usage: resolvepath [-hlp] path...
> # Version: 1.08
> #01
> function resolvepath # [-hlp] path...
> { set -o noglob
> # Ksh Bug: OPTIND cannot be declared integer!
> typeset -i rc
> typeset IFS OPTARG arg dir fn headers= symlink= oarg opt usepath=
> while getopts :HhLlPp opt
> do case $opt in
> (h) headers=ON ;;
> (+h|H) headers=OFF ;;
> (l) symlink=ON ;;
> (+l|L) symlink= ;;
> (p) usepath=ON ;;
> (+p|P) usepath= ;;
> ([:?]) print -ru2 "usage: $0 [-hlp] path...
> -h - prepend the output with argument header
> -l - show logical path with symlinks resolved [physical path]
> -p - apply path lookup, if applicable"
> return 2 ;;
> esac
> done
> shift OPTIND-1
> if [[ $headers = OFF ]]
> then headers=
> else (($#>1)) && headers=ON
> fi
> for arg
> do oarg=$arg
> if [[ $usepath = ON && ! -d $arg ]]
> then # Ksh Bug: "whence" cannot handle args with spaces
> arg=$(whence -p "$arg") ||
> { print -ru2 'resolvepath: whence: error:' \
> "\"$oarg\" not found"
> rc=rc+1 continue
> }
> fi
> [[ -a $arg ]] ||
> { print -ru2 "resolvepath: error: \"$arg\" not found"
> rc=rc+1 continue
> }
> [[ $arg != */* ]] && arg="./$arg"
> if [[ -d $arg ]]
> then dir=$arg fn=
> else dir=${arg%/*} fn=${arg##*/}
> fi
> ${DIAG:+print -ru2 "[ $0: dirpart=\"$dir\", filepart=\"$fn\" ]"}
> # Ksh Bug: "cd -P dir" works, but "cd -P -- dir" does not!
> [[ $dir = -* ]] && dir="./$dir" # work-around for above bug
> \cd ${symlink:+-P} "$dir" || rc=rc+1 continue
> print -r -- "${headers:+$oarg: }${PWD%/}/$fn" # <= TAB
> \cd - >&-
> done
> return $rc
> }
> #02 EMBEDDED MAN-PAGE FOR "src2man"
> : '
> #++
> NAME
> resolvepath - resolve and canonicize the full pathname of argument
> SYNOPSIS
> resolvepath [-hlp] path...
> OPTIONS
> -h - Prepend the output with argument header.
> -l - Show logical path with symlinks resolved. [physical path]
> -p - Apply path lookup, if applicable.
> DESCRIPTION
> ...
> If and only if the path is a directory, the output is guaranteed
> to be terminated with a slash ("/").
> RETURN CODE
> Returns 0 if successful, 2 for options parsing errors, otherwise
> the number of arguments in error.
> EXAMPLE
> $ resolvepath .
> /home/brian/side/lib/
> $ resolvepath cat
> resolvepath: error: "cat" not found
> $ resolvepath -p cat
> /bin/cat
> $ resolvepath -lp cat
> /usr/bin/cat
> $ resolvepath /
> /
> $ resolvepath //
> /
> $ resolvepath /..
> /
> $ resolvepath /.//..///.////../////.//////..///////.////////..
> /
> ENVIRONMENT
> PATH
> SEE ALSO
> predictshell(3S), stat(3S)
> AUTHOR
> CAVEATS
> The algorithm that is used requires the directory component of
> the resolved argument to be executable; i.e. you must have
> permission to chdir to it.
> BUGS
> Filenames with embedded spaces will be failed to be recognized;
> this is a bug in the ksh builtin "whence", not resolvepath(3S).
> #--
> '