What is the most direct way to convert a symlink into a regular file (i.e. a copy of the symlink target)?
cp filename filename-backup
mv filename-backup filename
There is no single command to convert a symlink to a regular file. The most direct way is to use
readlink to find the file a symlink points to, and then copy that file over the symlink:
cp --remove-destination `readlink bar.pdf` bar.pdf
Of course, if
bar.pdf is, in fact, a regular file to begin with, then this will clobber the file. Some sanity checking would therefore be advisable.