[bug-gv] updating pdf files by SIGHUP

[Rudolf Winter]

I'm trying to update a pdf file generated by pdflatex each time I run pdflatex 
while
leaving gv running.  When I change the latex file, gv fails when I run pdflatex 
with
the following error:

| Error: /syntaxerror in readxrefentry
| Operand stack:
|    --dict:5/5(L)--   --dict:5/5(L)--   false   --dict:5/5(L)--   160   1   0  
 1   0   n
| Execution stack:
|    %interp_exit   .runexec2   --nostringval--   --nostringval--   
--nostringval--   2   %stopped_push   --nostringval--   --nostringval--   
--nostringval--   false   1   %stopped_push   1   3   %oparray_pop   1   3   
%oparray_pop   1   3   %oparray_pop   .runexec2   --nostringval--   
--nostringval--   --nostringval--   2   %stopped_push   --nostringvalESP 
Ghostscript 7.07.1: Unrecoverable error, exit code 1
| --   --nostringval--   --nostringval--   --nostringval--   %loop_continue   
--nostringval--   --nostringval--   %loop_continue   --nostringval--   
--nostringval--   --nostringval--   --nostringval--   --nostringval--   
--nostringval--
| Dictionary stack:
|    --dict:1049/1417(ro)(G)--   --dict:0/20(G)--   --dict:73/200(L)--   
--dict:97/127(ro)(G)--   --dict:229/230(ro)(G)--   --dict:19/24(L)--   
--dict:4/6(L)--   --dict:19/20(L)--
| Current allocation mode is local

This happens reproducibly when I do this with a latex file such as bla.tex:

| \documentclass[a4paper]{article}
| \usepackage{a4}
| \usepackage{graphics}
| \begin{document}
| bla
| \end{document}

Here's what I do:

# compile once
pdflatex bla
# open gv
gv bla.pdf &
# get pid number of gv
gvpid=`ps -C gv -o pid=`
# edit latex file, e.g. add another line of text
vim bla.tex
# recompile
pdflatex bla
# send SIGHUP to gv to update
kill -SIGHUP $gvpid

which produces the error above.
--
Rudi Winter, Aberystwyth, Wales