Linux c 代码里的这个变量怎么来的？
现在手里的一份C-ICAP代码里，有这么一行代码：
char *SERVER_LOG_FILE = LOGDIR "/cicap-server.log";
bin/c-icap-config:9:#LOGDIR=
bin/c-icap-libicapapi-config:9:#LOGDIR=
c-icap:34:relink_command="(cd /home/svn_icap_src/icap/c_icap-0.2.5; { test -z "\${LIBRARY_PATH+set}" || unset LIBRARY_PATH || { LIBRARY_PATH=; export LIBRARY_PATH; }; }; { test -z "\${COMPILER_PATH+set}" || unset COMPILER_PATH || { COMPILER_PATH=; export COMPILER_PATH; }; }; { test -z "\${GCC_EXEC_PREFIX+set}" || unset GCC_EXEC_PREFIX || { GCC_EXEC_PREFIX=; export GCC_EXEC_PREFIX; }; }; { test -z "\${LD_RUN_PATH+set}" || unset LD_RUN_PATH || { LD_RUN_PATH=; export LD_RUN_PATH; }; }; LD_LIBRARY_PATH=:/home/www/unixODBC/lib; export LD_LIBRARY_PATH; PATH=/usr/kerberos/sbin:/usr/kerberos/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/home/www/unixODBC/bin/:/root/bin; export PATH; gcc -Iinclude/ -DCONFDIR=\\"/home/svn_icap_src/icap/c_icap-0.2.5/etc\\" -DMODSDIR=\\"/home/svn_icap_src/icap/c_icap-0.2.5/lib/c_icap/\\" -DSERVDIR=\\"/home/svn_icap_src/icap/c_icap-0.2.5/lib/c_icap/\\" -DLOGDIR=\\"/home/svn_icap_src/icap/c_icap-0.2.5/var/log/\\" -DDATADIR=\\"/home/svn_icap_src/icap/c_icap-0.2.5/share/c_icap/\\" -D_REENTRANT -g -O2 -Wall -D_FILE_OFFSET_BITS=64 -rdynamic -o \$progdir/\$file c_icap-aserver.o c_icap-request.o c_icap-cfg_param.o c_icap-proc_threads_queues.o c_icap-http_auth.o c_icap-access.o c_icap-log.o c_icap-service.o c_icap-module.o c_icap-commands.o c_icap-mpmt_server.o c_icap-dlib.o c_icap-info.o c_icap-default_acl.o -L/usr/local/json-c-0.9/lib ./.libs/libicapapi.so /usr/local/json-c-0.9/lib/libjson.so -Wl,-rpath -Wl,/home/svn_icap_src/icap/c_icap-0.2.5/.libs -Wl,-rpath -Wl,/usr/local/json-c-0.9/lib -Wl,-rpath -Wl,/home/svn_icap_src/icap/c_icap-0.2.5/lib -Wl,-rpath -Wl,/usr/local/json-c-0.9/lib)"
c-icap-config:9:#LOGDIR=
c-icap-config.in:9:#LOGDIR=
c-icap-libicapapi-config:9:#LOGDIR=
c-icap-libicapapi-config.in:9:#LOGDIR=
c_icap.mak:5:LOGDIR="c:\\c-icap\\log"
c_icap.mak:7:CI_DEFS=-DCONFDIR="$(CONFDIR)" -DSERVDIR="$(SERVDIR)" -DMODSDIR="$(MODSDIR)" -DLOGDIR="$(LOGDIR)"
docs/man/Makefile.am:6:LOGDIR=$(localstatedir)/log/
docs/man/Makefile.in:235:LOGDIR = $(localstatedir)/log/
docs/man/Makefile:235:LOGDIR = $(localstatedir)/log/
log.c:186:/*char *LOGS_DIR=LOGDIR;*/
log.c:187:char *SERVER_LOG_FILE = LOGDIR "/cicap-server.log";
log.c:188:/*char *ACCESS_LOG_FILE = LOGDIR "/cicap-access.log";*/
Makefile:356:LOGDIR = $(localstatedir)/log/
Makefile:383: -DSERVDIR="$(SERVICESDIR)" -DLOGDIR="$(LOGDIR)" \
Makefile:1614:$(mkinstalldirs) $(DESTDIR)$(LOGDIR);
Makefile:1616:chgrp nogroup $(DESTDIR)$(LOGDIR) || echo -e "*********\nWARNING! Can not set group for the log dir $(DESTDIR)$(LOGDIR)\n*********\n"
Makefile:1617:chmod 775 $(DESTDIR)$(LOGDIR)
Makefile.am:8:LOGDIR=$(localstatedir)/log/
Makefile.am:47: -DSERVDIR="$(SERVICESDIR)" -DLOGDIR="$(LOGDIR)" \
Makefile.am:100:$(mkinstalldirs) $(DESTDIR)$(LOGDIR);
Makefile.am:102:chgrp nogroup $(DESTDIR)$(LOGDIR) || echo -e "*********\nWARNING! Can not set group for the log dir $(DESTDIR)$(LOGDIR)\n*********\n"
Makefile.am:103:chmod 775 $(DESTDIR)$(LOGDIR)
Makefile.bak:356:LOGDIR = $(localstatedir)/log/
Makefile.bak:383: -DSERVDIR="$(SERVICESDIR)" -DLOGDIR="$(LOGDIR)" \
Makefile.bak:1614:$(mkinstalldirs) $(DESTDIR)$(LOGDIR);
Makefile.bak:1616:chgrp nogroup $(DESTDIR)$(LOGDIR) || echo -e "*********\nWARNING! Can not set group for the log dir $(DESTDIR)$(LOGDIR)\n*********\n"
Makefile.bak:1617:chmod 775 $(DESTDIR)$(LOGDIR)
Makefile.in:356:LOGDIR = $(localstatedir)/log/
Makefile.in:383: -DSERVDIR="$(SERVICESDIR)" -DLOGDIR="$(LOGDIR)" \
Makefile.in:1614:$(mkinstalldirs) $(DESTDIR)$(LOGDIR);
Makefile.in:1616:chgrp nogroup $(DESTDIR)$(LOGDIR) || echo -e "*********\nWARNING! Can not set group for the log dir $(DESTDIR)$(LOGDIR)\n*********\n"
Makefile.in:1617:chmod 775 $(DESTDIR)$(LOGDIR)
services/wkcash/Makefile.am:4:LOGDIR=$(localstatedir)/log/
services/wkcash/Makefile.am:9:srv_wkcash_la_CFLAGS= -I../../include/ -DLOGDIR="$(LOGDIR)" -DCONFDIR="$(CONFIGDIR)"
services/wkcash/Makefile.in:228:LOGDIR = $(localstatedir)/log/
services/wkcash/Makefile.in:231:srv_wkcash_la_CFLAGS = -I../../include/ -DLOGDIR="$(LOGDIR)" -DCONFDIR="$(CONFIGDIR)"
services/wkcash/Makefile:228:LOGDIR = $(localstatedir)/log/
services/wkcash/Makefile:231:srv_wkcash_la_CFLAGS = -I../../include/ -DLOGDIR="$(LOGDIR)" -DCONFDIR="$(CONFIGDIR)"
wk_access_log_path[0xff] = LOGDIR;
services/wkcash/srv_wkcash_log.c:21:char wk_access_log_path[0xff] = LOGDIR;
utils/Makefile.am:7:LOGDIR=$(localstatedir)/log/
utils/Makefile.in:247:LOGDIR = $(localstatedir)/log/
utils/Makefile:247:LOGDIR = $(localstatedir)/log/
