[tex4ht] How to control/optimize the number of times make4ht runs dvilualatex?

Michal Hoftich michal.h21 at gmail.com
Sun Apr 24 21:41:46 CEST 2022

Hi Nasser

> Unfortunately, I had to remove this build file after trying
> it on my actual large latex file.
> This is what happened. After waiting for almost 30 hrs, and counted
> tex4ht calling dvilualatex 10 times !  I decided it went into
> an infinite loop for some reason.  It takes 2-2.5 hrs for one
> call.

You are right, I had two bugs in the script! First is that the
compilation_count variable wasn't updated, so it is always 1, second
is that it compiles one time more than necessary even when I fixed
that issue. Try this version:

local htlatex = require "make4ht-htlatex"

local function get_checksum(main_file, extensions)
  -- make checksum for temporary files
  local checksum = ""
  local extensions = extensions or {"aux", "4tc", "xref"}
  for _, ext in ipairs(extensions) do
    local f = io.open(main_file .. "." .. ext, "r")
    if f then
      local content = f:read("*all")
      -- make checksum of the file and previous checksum
      -- this way, we will detect change in any file
      checksum = md5.sumhexa(checksum .. content)
  return checksum

Make:add("myhtlatex", function(par)
  -- get checksum of temp files before compilation
  local checksum = get_checksum(par.input)
  local status = htlatex.htlatex(par)
  -- stop processing on error
  if status ~= 0 then return status end
  -- get checksum after compilation
  local newchecksum = get_checksum(par.input)
  -- this is needed to prevent possible infinite loops
  local compilation_count = 1
  local max_compilations  = 3 -- <- change as you want
  while checksum ~= newchecksum do
    if compilation_count => max_compilations then return status end
    status = htlatex.htlatex(par)
    -- stop processing on error
    if status ~= 0 then return status end
    checksum = newchecksum
    -- get checksum after compilation
    newchecksum = get_checksum(par.input)
    compilation_count = compilation_count + 1
  return status

Make:myhtlatex {}


Best regards,

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