/etc/sysconfig/http under which apache.service read env setting

etc-sysconfig-http

#
# This file can be used to set additional environment variables for
# the httpd process, or pass additional options to the httpd
# executable.
#
# Note: With previous versions of httpd, the MPM could be changed by
# editing an "HTTPD" variable here.  With the current version, that
# variable is now ignored.  The MPM is a loadable module, and the
# choice of MPM can be changed by editing the configuration file
# /etc/httpd/conf.modules.d/00-mpm.conf.
#

#
# To pass additional options (for instance, -D definitions) to the
# httpd binary at startup, set OPTIONS here.
#
#OPTIONS=

#
# This setting ensures the httpd process is started in the "C" locale
# by default.  (Some modules will not behave correctly if
# case-sensitive string comparisons are performed in a different
# locale.)
#
LANG=C
[root@localhost sysconfig]# pwd
/etc/sysconfig