The -D Debug File Switch
The -D command-line switch
is used to redirect sendmail’s debugging output into a file
for later examination. It is used like this, where
file is the name of an
existing or new file:
-D fileThe -D command-line switch
(if used) must precede the -d switch on the same command line;
otherwise, the following error will print and all debugging
output will be printed to the standard output (possibly
causing you to miss seeing the error):
-D file must be before -d
The file specified with -D must live in a
directory that is writable by the user running sendmail. If the file
does not exist, it will be created. If the file already
exists, it will be silently appended to.
Extra care must be exercised when using the -D command-line switch as
root because the target file
will be appended to, even if it is a symbolic link to an
important file. For example, when /tmp/foo is a
non-root-owned symbolic link
that points to /etc/passwd, the following command line,
when run by root, will silently append debugging information
to the /etc/passwd
file:
# /usr/sbin/sendmail -D /tmp/foo -d0.1 -bt < /dev/nullGet sendmail, 4th Edition now with the O’Reilly learning platform.
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