+You may also specify the actual names of the compression algorithms, "XPRESS"
+and "LZX", instead of "fast" and "maximum", respectively.
+.TP
+\fB--threads\fR=\fINUM_THREADS\fR
+Number of threads to use for compressing data. Default: autodetect (number of
+processors). Note: if exporting to an uncompressed WIM, or exporting to a WIM
+with the same compression type as the source WIM, additional threads will not
+be used, regardless of this parameter, since no data compression needs to be
+done in these cases.
+.TP
+\fB--rebuild\fR
+When exporting image(s) to an existing WIM: rebuild the entire WIM rather than
+appending data to the end of it. Rebuilding the WIM is slower, but will save a
+little bit of space that would otherwise be left as a hole in the WIM. Also see
+\fB@IMAGEX_PROGNAME@ optimize\fR.
+.TP
+\fB--ref\fR="\fIGLOB\fR"
+File glob of additional split WIM parts that are part of the split WIM being
+exported. See \fBSPLIT_WIMS\fR.
+
+.SH SPLIT WIMS
+
+You may use \fB@IMAGEX_PROGNAME@ export\fR to export images from a split WIM. The
+\fISRC_WIMFILE\fR argument is used to specify the first part of the split WIM, and
+the \fB--refs\fR="\fIGLOB\fR" option is used to provide a shell-style file glob
+that specifies the additional parts of the split WIM. \fIGLOB\fR is expected to
+be a single string on the command line, so \fIGLOB\fR must be quoted so that it
+is protected against shell expansion. \fIGLOB\fR must expand to all parts of
+the split WIM, except optionally the first part which may either omitted or
+included in the glob (but the first part MUST be specified as \fISRC_WIMFILE\fR as
+well).
+
+Here's an example. The names for the split WIMs usually go something like:
+
+.RS
+.PP
+.nf
+mywim.swm
+mywim2.swm
+mywim3.swm
+mywim4.swm
+mywim5.swm
+.RE