Re: preliminary (but tested) latex_path patch

[Angus Leeming]

> Georg Baum wrote:
> It seems that dvips is a bit behind and does not understand
> quoted filenames.
Angus Leeming wrote:
> Yes, I say this last night.
>
> It's possible that a wrapper to dvips could get around this problem.
> Check out DTL (http://www.ctan.org/tex-archive/dviware/dtl/)
>
> It contains the utilities dv2dt and dt2dv to convert a DVI file to
> and from a human readable format.
Ok, attached is 'clean_dvi.sh' which manipulates the .dvi file 
produced by latex into a form that can be understood both by dvips and 
by yap (dvi viewer on Windows).

Usage:
$ sh clean_dvi.sh infile.dvi outfile.dvi
It requires the utilites dv2dt and dt2dv that I describe above.
From the script:
# It transpires that "quotes within the filename declaration
# confuse both dvips and yap (a dvi viewer on Windows).
# Entries in the .dtl file are of the form:
# ...PSfile=""a space".eps" llx=...
# Manipulate them to
# ...PSfile="a space.eps" llx=...
I built dv2dt and dt2dv without any problem and left them in 
$HOME/dtl. The script adds this directory to the PATH. You'll probably 
want to change that.

Running filename-test.dvi through this script allows me to view both 
the .dvi file in yap and the PostScript file generated by dvips.

I guess that I should rewrite it now in python for Windoze eejits 
without `sh` or `sed` and shove it on the wiki.

Regards,
Angus

#! /bin/sh
# clean_dvi modifies the input .dvi file so that
# dvips and yap (a dvi viewer on Windows) can find
# any embedded PostScript files whose names are protected with "-quotes.

# It works by:
# 1 translating the machine readable .dvi file to human readable .dtl form,
# 2 manipulating references to external files
# 3 translating the .dtl file back to .dvi format.

# It requires dv2dt and dt2dv from the DTL dviware package
# http://www.ctan.org/tex-archive/dviware/dtl/

find_exe() {
        # find_exe expects a single argument
        test $# -eq 1 || return 1

        # Some flavours of `which` return 1 on failure.
        output=`which "$1" 2>/dev/null` || return 1

        # Some flavours of `which` (eg Tru64 Unix's) report a failure
        # to find the executable to STDOUT with the message
        # 'no <exe> in ...'
        echo $output | grep '^no ' >/dev/null && return 1

        # Looks like we found the thing
        return 0
}


error() {
        echo "$@" >&2
        exit 1
}


usage() {
        echo "Usage: `basename $0` in.dvi out.dvi"
}


# First establish whether the require executables exist
# and that the expected information has been input on the
# command line.
PATH=$HOME/dtl:$PATH

find_exe dv2dt || error "Please install 'dv2dt'"
find_exe dt2dv || error "Please install 'dv2dt'"
find_exe sed   || error "Please install 'sed'"


test $# -eq 2 || error `usage $0`

INFILE="$1"
OUTFILE="$2"

# The sed script used to manipulate the DTL file
SEDCOMMANDS='

# It transpires that "quotes within the filename declaration
# confuse both dvips and yap (a dvi viewer on Windows).
# Entries in the .dtl file are of the form:
# ...PSfile=""a space".eps" llx=...
# Manipulate them to
# ...PSfile="a space.eps" llx=...

/PSfile=".*" llx/{

# Save the original in the hold space.
h

# Replace the file name with a placeholder "\n"
s/\(PSfile="\).*\(" llx=\)/\1\
\2/

# Exchange the contents of the hold and pattern space
x

# Remove everything except the filename
s/.*PSfile="//
s/" llx=.*//

# Remove any "-quotes in the filename
s/"//g

# Append the contents of the hold space to those of the pattern space
G

# Insert the modified file name (everything up to the first "\n")
# into the position of the placeholder (the second "\n").
s/\([^\n]*\)\n\([^\n]*\)\n/\2\1/
}'

# Manipulate the dvi file
dv2dt "$INFILE" | sed "$SEDCOMMANDS" | dt2dv -si "$OUTFILE" || exit 1

# The end