Sticky topic Template for syntax highlighting language wordfile lists both possibilities of assigning a syntax highlighting language to files: File Extensions = and File Names =

Wildcards are not possible with one exception: * as last "file extension" at end of File Extensions = results in highlighting all files not assigned to any syntax highlighting language with the language defined in the wordfile containing * at end of the file extension list.

It is not possible to assign "TOTO_ZUT_*_step*.txt" to a syntax highlighting language.

A solution is to use File Extensions = TXT in your wordfile and live with the fact that it highlights all *.txt files by default with the language defined in this wordfile. Selecting No Highlighting for an opened *.txt file is at any time possible. If this is acceptable for you depends mainly on how often you open and edit *.txt files which should not be highlighted with your syntax highlighting definition.

To avoid highlighting all *.txt with your wordfile for "TOTO_ZUT_*_step*.txt", it is possible to store your wordfile not in the default wordfiles directory %APPDATA%\IDMComp\UltraEdit\wordfiles\, but in a different directory. Next you use Project - New Project/Workspace, create a project for example in same directory as your wordfile, and specify in window opened with Project - Project Settings your wordfile to use for the project/workspace. This results in ignoring all standard wordfiles in default wordfiles directory whenever the workspace for working on "TOTO_ZUT_*_step*.txt" is opened.

You can open/close the workspace either via menu Project, or you create a shortcut to uedit32.exe with the additional parameters
/fni "complete path\project.prj"
which starts always a new instance of UltraEdit and opens the project/workspace.

The last option is to make a copy of %APPDATA%\IDMComp\UltraEdit\uedit32.ini in same directory, for example with name uedit32_txt.ini. Next you create a shortcut to uedit32.exe with the command line parameters
/fni /i="%APPDATA%\IDMComp\UltraEdit\uedit32_txt.ini"
Starting UltraEdit with this shortcut results in using the alternate INI file. The syntax highlighting wordfiles directory in UltraEdit started with the alternate INI file must be once configured to the directory containing your wordfile for "TOTO_ZUT_*_step*.txt" files.

Whenever you want to view/edit "TOTO_ZUT_*_step*.txt" files you need to use UltraEdit with the workspace respectively the alternate INI file to get them highlighted with the syntax highlighting definition in your wordfile while all other *.txt files opened in standard UltraEdit or with workspace not loaded are not highlighted at all or highlighted with a different wordfile for files with extension TXT.