t1lib
basically needs four types of files:
.afm
-files: These contain font metric descriptions as
well as kerning and ligature information for a particular font.
.pfa
-/.pfb
-files: These contain the character
outline descriptions. Type 1 font files may also lack any extension in their
filename. This is the habit on NeXTStep, for example.
.enc
-files: These contain encoding arrays in a special but
simple form. They are only needed if someone wants to load a special
encoding to reencode a font.
T1LIB_CONFIG
from
the program's environment.
The value of this variable is expected to be the
pathname of a configuration file for t1lib
.
T1LIB_CONFIG
exists, the file pointed to
by this variable will be tried to be opened. In case no environment
variable exists, the library will attempt to open a file called
.t1librc
in the user's home directory.
If this file as well does
not exist, the global configuration file t1lib.config
is tried to be
opened.1 If all these attempts to open a configuration file did not
succeed, all searchpaths are left at defaults (.
) and the font database
file is setup to be ./FontDataBase
. If this file cannot be
opened, the call to T1_InitLib()
returns a NULL-pointer thus
indicating an error condition. The program should then exit because
t1lib would not be able to do anything without an association of font
IDs to font files.