pdfapp: a pedestrian pdf concatenator

PDFAPP appends PDF files to a new PDF file

PDFAPP concatenates existing PDF files into
one PDF file using a user installed version
of GHOSTSCRIPT (GS).
in essence, it creates an input file @INPUT
for the GS application and runs it by a
call to SYSTEM().

see
> help pdfapp
for usage and a brief example for this small utility