"file name.tex" (for example), which
helps somewhat, but while this allows us to say
the analogous usage\input "foo bar.tex"
\includegraphics{"gappy graphics.eps"}
using “ordinary” LaTeX causes confusion in xdvi and
dvips, even though it works at compilation time. Sadly,
even within such quotes, multiple dots give \includegraphics
difficulties. Note that
\includegraphics{"gappy graphics.pdf"}
works in a similar version of PDFTeX.
If you’re using the graphics package, the grffile
package will help. The package offers several options, the simplest
of which are multidot (allowing more than one dot in a
file name) and space (allowing space in a file name). The
space option requires that you’re running on a
sufficiently recent version of PDFTeX, in PDF mode — and
even then it won’t work for MetaPost files, which are read as TeX
input, and therefore use the standard input mechanism).
This question on the Web: http://www.tex.ac.uk/cgi-bin/texfaq2html?label=grffilenames