diff --git a/fuse/main.c b/fuse/main.c
index effe5c5..30dd900 100644
--- a/fuse/main.c
+++ b/fuse/main.c
@@ -17,7 +17,7 @@
  */
 
 #define _POSIX_C_SOURCE 200809L // for strdup and struct timespec
-#define _BSD_SOURCE             // for strdup on old systems
+#define _DEFAULT_SOURCE         // for strdup on old systems
 #define _GNU_SOURCE             // for getline on old systems
 
 #define FUSE_USE_VERSION 30
diff --git a/mfapi/apicalls/upload_patch.c b/mfapi/apicalls/upload_patch.c
index d3d7689..614b0ed 100644
--- a/mfapi/apicalls/upload_patch.c
+++ b/mfapi/apicalls/upload_patch.c
@@ -18,7 +18,7 @@
  */
 
 #define _POSIX_C_SOURCE 200809L // for strdup
-#define _BSD_SOURCE             // for strdup on old systems
+#define _DEFAULT_SOURCE         // for strdup on old systems
 
 #include <jansson.h>
 #include <stdlib.h>
diff --git a/mfapi/apicalls/upload_simple.c b/mfapi/apicalls/upload_simple.c
index 3682b92..29e6934 100644
--- a/mfapi/apicalls/upload_simple.c
+++ b/mfapi/apicalls/upload_simple.c
@@ -18,7 +18,7 @@
  */
 
 #define _POSIX_C_SOURCE 200809L // for strdup
-#define _BSD_SOURCE             // for strdup on old systems
+#define _DEFAULT_SOURCE         // for strdup on old systems
 
 #include <jansson.h>
 #include <stdlib.h>
diff --git a/mfapi/apicalls/user_get_session_token.c b/mfapi/apicalls/user_get_session_token.c
index 36571f8..0c22fc6 100644
--- a/mfapi/apicalls/user_get_session_token.c
+++ b/mfapi/apicalls/user_get_session_token.c
@@ -18,7 +18,7 @@
  */
 
 #define _POSIX_C_SOURCE 200809L // for strdup
-#define _BSD_SOURCE             // for strdup on old systems
+#define _DEFAULT_SOURCE         // for strdup on old systems
 
 #include <jansson.h>
 #include <stdint.h>
diff --git a/mfapi/file.c b/mfapi/file.c
index ba540c4..7de59cb 100644
--- a/mfapi/file.c
+++ b/mfapi/file.c
@@ -18,7 +18,7 @@
  */
 
 #define _POSIX_C_SOURCE 200809L // for strdup
-#define _BSD_SOURCE             // for strdup on old systems
+#define _DEFAULT_SOURCE         // for strdup on old systems
 
 #include <stdint.h>
 #include <stdio.h>
diff --git a/mfapi/mfconn.c b/mfapi/mfconn.c
index d7b2270..b3705f4 100644
--- a/mfapi/mfconn.c
+++ b/mfapi/mfconn.c
@@ -18,7 +18,7 @@
  */
 
 #define _POSIX_C_SOURCE 200809L // for strdup
-#define _BSD_SOURCE             // for strdup on old systems
+#define _DEFAULT_SOURCE         // for strdup on old systems
 
 #include <openssl/md5.h>
 #include <openssl/sha.h>
diff --git a/mfapi/patch.c b/mfapi/patch.c
index ac056b8..aab8d3c 100644
--- a/mfapi/patch.c
+++ b/mfapi/patch.c
@@ -17,7 +17,7 @@
  */
 
 #define _POSIX_C_SOURCE 200809L // for strdup
-#define _BSD_SOURCE             // for strdup on old systems
+#define _DEFAULT_SOURCE         // for strdup on old systems
 
 #include <stdint.h>
 #include <openssl/sha.h>
diff --git a/mfshell/mfshell.c b/mfshell/mfshell.c
index 1fc8fcb..d3ccff9 100644
--- a/mfshell/mfshell.c
+++ b/mfshell/mfshell.c
@@ -19,7 +19,7 @@
 
 #ifdef __linux
 #define _POSIX_C_SOURCE 200809L // for strdup and getline
-#define _BSD_SOURCE             // for strsep
+#define _DEFAULT_SOURCE         // for strsep
 #else
 #define _WITH_GETLINE           // on freebsd for getline
 #endif
diff --git a/utils/stringv.c b/utils/stringv.c
index e032a52..82fbd33 100644
--- a/utils/stringv.c
+++ b/utils/stringv.c
@@ -17,7 +17,7 @@
  */
 
 #define _POSIX_C_SOURCE 200809L // for strdup
-#define _BSD_SOURCE             // for strdup on old systems
+#define _DEFAULT_SOURCE         // for strdup on old systems
 
 #include <stdio.h>
 #include <stdlib.h>