The EX_OSFILE exit code (value 72) results
when certain system files could not be opened and when certain system
programs could not be executed.
When sendmail gets a SIGHUP signal, it attempts
to re-execute itself (SIGHUP). If it fails, the
following error is logged and sendmail exits:
could not exec /path/sendmail: reason
The sendmail program can run a program to look
up a key in a database. If
sendmail fails to run the program, it prints the
following error:
prog_map_lookup(program) failed (reason) -- closing
We probably don't have to mention this, but the
sendmail program has to read its configuration
file. If it fails to open, stat, or read that file, or if that file
is not a plain file, it prints one of the following errors (depending
on your version of sendmail) and exits with an
EX_OSFILE value:
cannot open
cannot fstat
not a plain file
I/O read error
filename: cannot open reason
filename: cannot fstat reason
filename: not a plain file reason
filename: I/O read error reason
