exit

### Placement of the Bookkeeping File

To cut down on the time invested to locate ﬁles, the tex4ht.c program maintains a bookkeeping ﬁle where it records the addresses of the ﬁles it ﬁnds. Whenever the program needs to locate a ﬁle, it ﬁrst searches the address in the bookkeeping ﬁle. If it doesn’t ﬁnd the address there, the program embarks on a search throughout the physical directories of its platform.

The program places the bookkeeping ﬁle at the ﬁrst applicable location of the following list.

1. The pointer speciﬁed by an optional ‘-l’ switch provided to the invocation of the tex4ht program.
2. A ﬁle named tex4ht.fls in the directory speciﬁed by an optional environment variable named TEX4HTWR.
3. The location speciﬁed by an optional ‘l’ record provided in the environment ﬁle.
4. A ﬁle named tex4ht.fls in the work directory.

A given address may start with the character ‘~’ or the character pair ‘~~’. The single character ‘~’ is interpreted to be the directory address of the root, provided in an environment variable named HOME. The character pair ‘~~’ is interpreted to be a directory address provided in an environment variable named TEX4HTWR. The address stored in the latter environment variable may also start with a single character ‘~’.

The bookkeeping ﬁle must have writable access mode, and the directory which contains the ﬁle should have a compatible access mode. On multi-user platforms, it is recommended not to share the bookkeeping ﬁle, but to ask for such ﬁles in the users’ directories.

The bookkeeping ﬁle is a dynamically constructed variant of the ls-R ﬁle of kpathsea. TeX4ht ignores its own bookkeeping mechanism, if the program tex4ht.c is compiled with a raised -DKPATHSEA switch.