CTAN Comprehensive TeX Archive Network

Directory macros/latex/contrib/snapshot

README file for package snapshot 2.14 [2020/06/17]

Copyright 1999-2003, 2004, 2010, 2012, 2020 American Mathematical Society.

This work may be distributed and/or modified under the
conditions of the LaTeX Project Public License, either version 1.3c
of this license or (at your option) any later version.
The latest version of this license is in
and version 1.3c or later is part of all distributions of LaTeX
version 2005/12/01 or later.

This work has the LPPL maintenance status `maintained'.

The Current Maintainer of this work is the American Mathematical

American Mathematical Society
Technical Support
Publications Technical Group
201 Charles Street
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tel: (401) 455-4080
     (800) 321-4267 (USA and Canada only)
fax: (401) 331-3842
email: tech-support@ams.org



Complete documentation of all package options is available in

Typical usage involves the following steps:

1. Add a \RequirePackage statement at the top of the document:




       hello, world


   Note that snapshot should be the very first thing loaded, even
   before the \documentclass.  Otherwise snapshot will not be able to
   capture the information for the document class and any packages
   loaded inside it.

2. Run LaTeX on the document. This will produce a dependency list in a
   file \jobname.dep.

3. Insert the .dep file at the top of the document, before
   \documentclass. The following example shows what you would
   typically end up with for a document that used the article
   documentclass and the graphicx package:


         *{application}{pdfTeX}  {0000/00/00 v1.40.21}
         *{format} {LaTeX2e}     {2020-02-02 v2.e}
         *{package}{snapshot}    {2020/06/17 v2.14}
         *{class}  {article}     {2019/12/20 v1.4l}
         *{file}   {size10.clo}  {2019/12/20 v1.4l}
         *{package}{graphicx}    {2019/11/30 v1.2a}
         *{package}{keyval}      {2014/10/28 v1.15}
         *{package}{graphics}    {2019/11/30 v1.4a}
         *{package}{trig}        {2016/01/03 v1.10}
         *{file}   {graphics.cfg}{2016/06/04 v1.11}
         *{file}   {dvips.def}   {2017/06/20 v3.1d}
         *{file}   {l3backend-dvips.def}{2020-05-05 v3}


   Now each time you recompile the document, snapshot will compare the
   list of files actually loaded against the list recorded in
   \RequireVersions and warn you of any changes.


Since the snapshot package was originally released, there has been a
tremendous amount of evolution among TeX engines (what snapshot calls
the "application").  In addition to the introduction of two major new
engines, three other engines that were once distinct have effectively
merged.  The algorithm for detecting the identify of the engine has
been updated to reflect the state of the TeX world as reflected in TeX
Live 2020.

COMPATIBILITY NOTE: As a result of these improvements, the
*{application} entry of your documents will almost certainly change.
The snapshot package does not warn of changes in this entry, but if
you have an external application that makes use of this information,
you will probably need to update it.


2020-06-17 snapshot.dtx v2.14
    -- Added code to detect the aleph, ptex, eptex, uptex, euptex,
       luatex, and xetex engines in addition to etex, pdftex, and
       pdfetex.  Also distinguish between the various engines which
       incorporate the eTeX extensions.
    -- Made snapshot more tolerant of macros in the optional argument
       to \Provides... declarations.

Download the contents of this package in one zip archive (246.3k).

snapshot – List the external dependencies of a document

The snapshot package helps the owner of a document obtain a list of the external dependencies of the document, in a form that can be embedded at the top of the document. It provides a snapshot of the current processing context of the document, insofar as it can be determined from inside . If a document contains such a dependency list, then it becomes possible to arrange that the document be processed always with the same versions of everything, in order to ensure the same output. This could be useful for someone wanting to keep a document on hand and consistently reproduce an identical DVI file from it, on the fly; or for someone wanting to shield a document during the final stages of its production cycle from unexpected side effects of routine upgrades to the system.

Home pagehttps://www.ams.org/arc/resources/snapshot-about.html
LicensesThe Project Public License 1.3c
MaintainerThe American Mathematical Society
Michael J. Downes (deceased)
Contained inTeX Live as snapshot
MiKTeX as snapshot
File management
See alsobundledoc
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