Further to my Lilypond woes...
Lilypond is installed (I just had to re-install it but that's another issue) and there is a lilypond shell script as promised in my /home/mark/bin folder
mark@mark-GA-MA785GMT-UD2H:~$ ls /home/mark/bin
abc2ly lilypond-book midi2ly sfarkxtc
convert-ly lilypond-invoke-editor mup2ly uninstall-lilypond
etf2ly lilypond-wrapper.guile musicxml2ly
lilypond lilypond-wrapper.python RealPlayer10GOLD.bin
and this folder is the first one in the PATH variable
mark@mark-GA-MA785GMT-UD2H:~$ echo $PATH
but bash isn't finding it there
mark@mark-GA-MA785GMT-UD2H:~$ lilypond O_Sacrum_Convivium_MC
bash: /usr/bin/lilypond: No such file or directory
It runs fine if I specify the directory for the command
mark@mark-GA-MA785GMT-UD2H:~$ /home/mark/bin/lilypond O_Sacrum_Convivium_MC
GNU LilyPond 2.14.2
etc. so this isn't insuperable, but am I missing something obvious or should this not be happening? Thanks.