Because I began to use many Unicode characters (Japanese, some unusual diacritics, etc.) I switched from LaTeX to XeLaTeX to render my documents. Unfortunately, if a font is missing, the letters are simply left out (for example, when I had forgotten to specify the font for Japanese) without any error (and I can't seem to spot a warning either). I will read the result, but I prefer to get some early warning if some character isn't available. Is there any way to get a warning about characters that have not been rendered? An error would be even better.
The log should list all missing characters in the form of:
It is easy. Just try:
In the example above I used
Edit1: Based on Khaled comments "If there is a missing glyph in the font XeTeX will show the .notdef glyph, most fonts have a .notdef glyph with non zero height and width". So we can perform a furthur test with characters from a script that is unlikely to be found in every font. Say, Avestan (an ancient Iranian script). Being a Zoroastrian myself, there are only few unicode fonts that contain Avestan chracters. So let's try (although there may be a better approach):
Edit2: It seems that my previous answers was not needed because etex provides
An example would be: