Add WITHOUTURL to build system, prefer /usr/bin/curl-config

Author: chad-earthscope

Makefile

@@ -1,10 +1,19 @@
 # Automatically configure URL support if libcurl is present
-# Test for curl-config command and add build options if so
-ifneq (,$(shell command -v curl-config))
-        export LM_CURL_VERSION=$(shell curl-config --version)
-        export CFLAGS:=$(CFLAGS) -DLIBMSEED_URL
-        export LDFLAGS:=$(LDFLAGS) $(shell curl-config --libs)
-        $(info Configured with $(LM_CURL_VERSION))
+# Test for curl-config command and add build options if found
+# Prefer /usr/bin/curl-config over any other curl-config
+ifndef WITHOUTURL
+  ifneq (,$(wildcard /usr/bin/curl-config))
+     CURL_CONFIG := /usr/bin/curl-config
+  else ifneq (,$(shell command -v curl-config))
+     CURL_CONFIG := $(shell command -v curl-config)
+  endif
+endif
+
+ifneq (,$(CURL_CONFIG))
+  export LM_CURL_VERSION=$(shell $(CURL_CONFIG) --version)
+  export CFLAGS:=$(CFLAGS) -DLIBMSEED_URL
+  export LDFLAGS:=$(LDFLAGS) $(shell $(CURL_CONFIG) --libs)
+  $(info Configured with $(LM_CURL_VERSION))
 endif
 
 .PHONY: all clean