[Tex/LaTex] File ended while scanning use of \@writefile

compiling

My problem is that if I try to recompile a text after correction of some mistake, e.g. missing "}", the I get a message

Runaway argument?
{\contentsline {figure}{\numberline {\relax 3.9}{\ignorespaces
! File ended while scanning use of \@writefile.

\par
l.128 \begin{document}

Then I delete the *.aux file and other auxiliary files and so I can recompile without any problem. Howewer if again I get a mistake, compile the text,get an error message, stop compiling, fix an error in the text and try to recompile, again I will get the same "File ended while scanning use of \@writefile." and again the only one way is to delete the auxiliary files. Any suggestions how to fix the problem?

Best Answer

Use

\caption{Scheme of GI off-specular scattering kinematics. 
         Modified from~\protect\cite{Zabel2007handbook}}%%%<---
\label{Off-Spec_Kinematics}

and delete all helper files before running LaTeX again.

Related Solutions

[Tex/LaTex] LaTeX is compiling the file from before changes

This is a property of LaTeX itself. Some of the information in .aux file is sensitive to changes in the document, especially changes in:

babel loading and languages
hyperref loading

If you consider it simplest to use the same file name, I recommend you to always run LaTeX on this simple document in between:

\batchmode
\documentclass{article}
\begin{document}
Hello World!
\end{document}

It should clear the information in the auxiliary files and everything should run smoothly.

Obviously, much simpler solution is to use the TeXworks built-in command

File -> Remove Aux Files...

whenever you paste a new MWE.

[Tex/LaTex] Unclean .aux file causes “file ended while scanning use of \@newl@bel” error. Why is it not purged

With the help of When is the aux file read and written? and Barbara Beetons kind assistance I was able to determine what goes wrong and how to prevent it.

This is the problem:

Normally I then don't work with the TeX engine on the console, but simply correct my error and restart.

This is what I should have done on the console:

Type ?+Return to get an idea of what can be done.
Simply hit Return repeatedly until Tex is finished.
Type X+Return to finish the run immediately.
Type E+Return to have the cursor jump to the point where the error occurred.

What happens is, that TeX buffers the \write commands to the .aux file in two stages. First stage, it waits until a page is shipped out to get the page numbers right. Second stage, it waits until it sees fit to issue a write() system call, to reduce the number of (potentially slow) system calls. This second buffer seemingly does not care, if the chunks it writes to file are self-contained legal TeX since it will complete the file before the TeX run is finished anyway.

In the environment of TeXShop however it is tempting to let TeX hang unfinished after an error. Thus the second output puffer is not flushed and the .aux file possibly left unfinished and in an illegal state.

My personal conclusion from this: Always let TeX finish.

The assumption that TeX will have a chance to finish it's run after it stopped for an error was very reasonable before windowed environments, where it became easy and normal to leave processes hanging in the background.

Things that could be done on software side to facilitate this user behavior:

Change Tex's second buffer behavior to issue a write() system call in case of an error or to break only into TeX-legal chunks.
Adjust the environment (TexShop) to either clean the .aux file after a process abortion or provide default input to always correctly finish the process.

Things that the user can do, other than always letting TeX finish:

Use \include{...}. That way the .aux files of the sections before are closed an finished by the time the error occurs. Chances are the .aux file of your current section isn't large enough yet and no TeX-illegal parts were written.
Hack something involving \immediate\closeout\@mainaux followed by an \openout\@mainaux and a copy of the contents so they don't get overwritten. This will effectively flush the output buffer. Does not seem worth the effort though.