Environment$SYSTEMD_PAGERPager to use when is not given; overrides
$PAGER. If neither $SYSTEMD_PAGER nor $PAGER are set, a
set of well-known pager implementations are tried in turn, including
less1 and
more1, until one is found. If
no pager implementation is discovered no pager is invoked. Setting this environment variable to an empty string
or the value cat is equivalent to passing .$SYSTEMD_LESSOverride the options passed to less (by default
FRSXMK).Users might want to change two options in particular:This option instructs the pager to exit immediately when
CtrlC is pressed. To allow
less to handle CtrlC
itself to switch back to the pager command prompt, unset this option.If the value of $SYSTEMD_LESS does not include K,
and the pager that is invoked is less,
CtrlC will be ignored by the
executable, and needs to be handled by the pager.This option instructs the pager to not send termcap initialization and deinitialization
strings to the terminal. It is set by default to allow command output to remain visible in the
terminal even after the pager exits. Nevertheless, this prevents some pager functionality from
working, in particular paged output cannot be scrolled with the mouse.See
less1
for more discussion.$SYSTEMD_LESSCHARSETOverride the charset passed to less (by default utf-8, if
the invoking terminal is determined to be UTF-8 compatible).$SYSTEMD_PAGERSECURETakes a boolean argument. When true, the "secure" mode of the pager is enabled; if
false, disabled. If $SYSTEMD_PAGERSECURE is not set at all, secure mode is enabled
if the effective UID is not the same as the owner of the login session, see geteuid2 and
sd_pid_get_owner_uid3.
In secure mode, will be set when invoking the pager, and the pager shall
disable commands that open or create new files or start new subprocesses. When
$SYSTEMD_PAGERSECURE is not set at all, pagers which are not known to implement
secure mode will not be used. (Currently only
less1 implements
secure mode.)Note: when commands are invoked with elevated privileges, for example under sudo8 or
pkexec1, care
must be taken to ensure that unintended interactive features are not enabled. "Secure" mode for the
pager may be enabled automatically as describe above. Setting SYSTEMD_PAGERSECURE=0
or not removing it from the inherited environment allows the user to invoke arbitrary commands. Note
that if the $SYSTEMD_PAGER or $PAGER variables are to be
honoured, $SYSTEMD_PAGERSECURE must be set too. It might be reasonable to completely
disable the pager using instead.$SYSTEMD_COLORSThe value must be a boolean. Controls whether colorized output should be
generated. This can be specified to override the decision that systemd makes based
on $TERM and what the console is connected to.$SYSTEMD_URLIFYThe value must be a boolean. Controls whether clickable links should be generated in
the output for terminal emulators supporting this. This can be specified to override the decision that
systemd makes based on $TERM and other conditions.