diff --git a/Makefile b/Makefile
index c88d6f3..b2eee20 100644
--- a/Makefile
+++ b/Makefile
@@ -13,7 +13,7 @@
 CXX = c++
 STRIP = strip
 CXXFLAGS = -std=c++20 -s -Wall -Wextra -Wpedantic -O2 -march=native -D_POSIX_C_SOURCE=200809L -D_DEFAULT_SOURCE
-CPPFLAGS = -I/usr/local/include -I. -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE
+CPPFLAGS = -I/usr/local/include -I. -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -D_XOPEN_SOURCE=700
 LDFLAGS = -s
 LDLIBS = -L/usr/local/lib -lcurl -lreadline
 
@@ -75,4 +75,4 @@ debug:
 32bit:
 	$(MAKE) CXXFLAGS="$(CXXFLAGS) -m32" LDFLAGS="$(LDFLAGS) -m32" bantam
 
-.PHONY: clean install debug 32bit
\ No newline at end of file
+.PHONY: clean install debug 32bit