diff --git a/headers/compatibility/bsd/arpa/ftp.h b/headers/compatibility/bsd/arpa/ftp.h
index 9a36488540..38f9772ba2 100644
--- a/headers/compatibility/bsd/arpa/ftp.h
+++ b/headers/compatibility/bsd/arpa/ftp.h
@@ -36,6 +36,10 @@
 #ifndef _ARPA_FTP_H_
 #define	_ARPA_FTP_H_
 
+
+#ifdef _BSD_SOURCE
+
+
 /* Definitions for FTP; see RFC-765. */
 
 /*
@@ -106,4 +110,8 @@ char *modenames[] =  {"0", "Stream", "Block", "Compressed" };
 
 #define	BLK_BYTECOUNT	2	/* Bytes in this block */
 
+
+#endif
+
+
 #endif /* !_FTP_H_ */
diff --git a/headers/compatibility/bsd/arpa/telnet.h b/headers/compatibility/bsd/arpa/telnet.h
index dd941c7e70..3055a551f8 100644
--- a/headers/compatibility/bsd/arpa/telnet.h
+++ b/headers/compatibility/bsd/arpa/telnet.h
@@ -37,6 +37,10 @@
 #ifndef _ARPA_TELNET_H_
 #define	_ARPA_TELNET_H_
 
+
+#ifdef _BSD_SOURCE
+
+
 /*
  * Definitions for the TELNET protocol.
  */
@@ -344,4 +348,8 @@ extern char *enctype_names[];
 #define	ENCTYPE_NAME_OK(x)	((unsigned int)(x) < ENCTYPE_CNT)
 #define	ENCTYPE_NAME(x)		enctype_names[x]
 
+
+#endif
+
+
 #endif /* !_TELNET_H_ */
diff --git a/headers/compatibility/bsd/arpa/tftp.h b/headers/compatibility/bsd/arpa/tftp.h
index 1de4dd48a9..10880f3f8d 100644
--- a/headers/compatibility/bsd/arpa/tftp.h
+++ b/headers/compatibility/bsd/arpa/tftp.h
@@ -37,6 +37,10 @@
 #ifndef _ARPA_TFTP_H_
 #define	_ARPA_TFTP_H_
 
+
+#ifdef _BSD_SOURCE
+
+
 /*
  * Trivial File Transfer Protocol (IEN-133)
  */
@@ -80,4 +84,8 @@ struct tftphdr {
 #define	ENOUSER		7		/* no such user */
 #define	EOPTNEG		8		/* option negotiation failed */
 
+
+#endif
+
+
 #endif /* !_TFTP_H_ */
diff --git a/headers/compatibility/bsd/err.h b/headers/compatibility/bsd/err.h
index 1f0ff6fbe5..8396c680dd 100644
--- a/headers/compatibility/bsd/err.h
+++ b/headers/compatibility/bsd/err.h
@@ -37,6 +37,10 @@
 #ifndef _ERR_H_
 #define	_ERR_H_
 
+
+#ifdef _BSD_SOURCE
+
+
 /*
  * Don't use va_list in the err/warn prototypes.   Va_list is typedef'd in two
  * places (<machine/varargs.h> and <machine/stdarg.h>), so if we include one
@@ -69,4 +73,8 @@ void	err_set_file(void *);
 void	err_set_exit(void (*)(int));
 __END_DECLS
 
+
+#endif
+
+
 #endif /* !_ERR_H_ */
diff --git a/headers/compatibility/bsd/errno.h b/headers/compatibility/bsd/errno.h
index 99d415ad65..3ae5026680 100644
--- a/headers/compatibility/bsd/errno.h
+++ b/headers/compatibility/bsd/errno.h
@@ -9,6 +9,13 @@
 #include_next <errno.h>
 
 
+#ifdef _BSD_SOURCE
+
+
 #define EDOOFUS	EINVAL
 
+
+#endif
+
+
 #endif	/* _BSD_ERRNO_H_ */
diff --git a/headers/compatibility/bsd/histedit.h b/headers/compatibility/bsd/histedit.h
index 89f3af7987..216a9f10d5 100644
--- a/headers/compatibility/bsd/histedit.h
+++ b/headers/compatibility/bsd/histedit.h
@@ -40,6 +40,10 @@
 #ifndef _HISTEDIT_H_
 #define	_HISTEDIT_H_
 
+
+#ifdef _BSD_SOURCE
+
+
 #include <sys/cdefs.h>
 #include <sys/types.h>
 #include <stdio.h>
@@ -225,4 +229,8 @@ int		 tok_str(Tokenizer *, const char *,
 
 __END_DECLS
 
+
+#endif
+
+
 #endif /* _HISTEDIT_H_ */
diff --git a/headers/compatibility/bsd/ifaddrs.h b/headers/compatibility/bsd/ifaddrs.h
index e02be83964..2716a709f6 100644
--- a/headers/compatibility/bsd/ifaddrs.h
+++ b/headers/compatibility/bsd/ifaddrs.h
@@ -6,6 +6,9 @@
 #define _IFADDRS_H
 
 
+#ifdef _BSD_SOURCE
+
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -32,4 +35,7 @@ void freeifaddrs(struct ifaddrs *ifa);
 #endif
 
 
+#endif
+
+
 #endif
diff --git a/headers/compatibility/bsd/libutil.h b/headers/compatibility/bsd/libutil.h
index ee1ff01691..2add799326 100644
--- a/headers/compatibility/bsd/libutil.h
+++ b/headers/compatibility/bsd/libutil.h
@@ -39,6 +39,10 @@
 #ifndef _LIBUTIL_H_
 #define	_LIBUTIL_H_
 
+
+#ifdef _BSD_SOURCE
+
+
 #include <stdint.h>
 #include <sys/cdefs.h>
 #include <sys/types.h>
@@ -162,4 +166,8 @@ __END_DECLS
 #define HN_GETSCALE		0x10
 #define HN_AUTOSCALE		0x20
 
+
+#endif
+
+
 #endif /* !_LIBUTIL_H_ */
diff --git a/headers/compatibility/bsd/netinet/in_systm.h b/headers/compatibility/bsd/netinet/in_systm.h
index 068f6808a9..41d68f43f7 100644
--- a/headers/compatibility/bsd/netinet/in_systm.h
+++ b/headers/compatibility/bsd/netinet/in_systm.h
@@ -6,6 +6,9 @@
 #define _NETINET_IN_SYSTM_H_
 
 
+#ifdef _BSD_SOURCE
+
+
 #include <stdint.h>
 
 
@@ -14,4 +17,7 @@ typedef uint32_t n_long;
 typedef uint32_t n_time;
 
 
+#endif
+
+
 #endif	/* _NETINET_IN_SYSTM_H_ */
diff --git a/headers/compatibility/bsd/paths.h b/headers/compatibility/bsd/paths.h
index dcc51a59d8..75998686a2 100644
--- a/headers/compatibility/bsd/paths.h
+++ b/headers/compatibility/bsd/paths.h
@@ -37,6 +37,10 @@
 #ifndef _PATHS_H_
 #define	_PATHS_H_
 
+
+#ifdef _BSD_SOURCE
+
+
 #include <sys/cdefs.h>
 
 /* Default search path. */
@@ -136,4 +140,8 @@ __END_DECLS
 #define	_PATH_WALL	"/rescue/wall"
 #endif /* RESCUE */
 
+
+#endif
+
+
 #endif /* !_PATHS_H_ */
diff --git a/headers/compatibility/bsd/pty.h b/headers/compatibility/bsd/pty.h
index 441cecdbbd..2ef64ff593 100644
--- a/headers/compatibility/bsd/pty.h
+++ b/headers/compatibility/bsd/pty.h
@@ -6,6 +6,9 @@
 #define _BSD_PTY_H_
 
 
+#ifdef _BSD_SOURCE
+
+
 #include <sys/cdefs.h>
 #include <termios.h>
 
@@ -20,4 +23,8 @@ extern pid_t	forkpty(int* master, char* name,
 
 __END_DECLS
 
+
+#endif
+
+
 #endif	// _BSD_PTY_H_
diff --git a/headers/compatibility/bsd/signal.h b/headers/compatibility/bsd/signal.h
index 7337ea38dc..58f16bb7cc 100644
--- a/headers/compatibility/bsd/signal.h
+++ b/headers/compatibility/bsd/signal.h
@@ -9,6 +9,9 @@
 #include_next <signal.h>
 
 
+#ifdef _BSD_SOURCE
+
+
 #define	sigmask(sig) (1 << ((sig) - 1))
 
 
@@ -23,4 +26,8 @@ int sigblock(int mask);
 }
 #endif
 
+
+#endif
+
+
 #endif	/* _BSD_SIGNAL_H_ */
diff --git a/headers/compatibility/bsd/stdio.h b/headers/compatibility/bsd/stdio.h
index 7a48b0f707..5f80fc087c 100644
--- a/headers/compatibility/bsd/stdio.h
+++ b/headers/compatibility/bsd/stdio.h
@@ -9,6 +9,9 @@
 #include_next <stdio.h>
 
 
+#ifdef _BSD_SOURCE
+
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -19,4 +22,8 @@ char *fgetln(FILE *stream, size_t *_length);
 }
 #endif
 
+
+#endif
+
+
 #endif	/* _BSD_STDIO_H_ */
diff --git a/headers/compatibility/bsd/stdlib.h b/headers/compatibility/bsd/stdlib.h
index f06312605d..d65871f812 100644
--- a/headers/compatibility/bsd/stdlib.h
+++ b/headers/compatibility/bsd/stdlib.h
@@ -9,6 +9,9 @@
 #include_next <stdlib.h>
 
 
+#ifdef _BSD_SOURCE
+
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -21,4 +24,8 @@ void		setprogname(const char *programName);
 }
 #endif
 
+
+#endif
+
+
 #endif	/* _BSD_STDLIB_H_ */
diff --git a/headers/compatibility/bsd/string.h b/headers/compatibility/bsd/string.h
index dd508b9150..7d194971d1 100644
--- a/headers/compatibility/bsd/string.h
+++ b/headers/compatibility/bsd/string.h
@@ -9,6 +9,9 @@
 #include_next <string.h>
 
 
+#ifdef _BSD_SOURCE
+
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -19,4 +22,8 @@ char* strsep(char** string, const char* delimiters);
 }
 #endif
 
+
+#endif
+
+
 #endif	/* _BSD_STRING_H_ */
diff --git a/headers/compatibility/bsd/stringlist.h b/headers/compatibility/bsd/stringlist.h
index 52a121c24b..ee1cf13be7 100644
--- a/headers/compatibility/bsd/stringlist.h
+++ b/headers/compatibility/bsd/stringlist.h
@@ -35,6 +35,11 @@
 
 #ifndef _STRINGLIST_H
 #define _STRINGLIST_H 
+
+
+#ifdef _BSD_SOURCE
+
+
 #include <sys/cdefs.h>
 #include <sys/types.h>
 
@@ -54,4 +59,8 @@ void	 sl_free(StringList *, int);
 char	*sl_find(StringList *, char *);
 __END_DECLS
 
+
+#endif
+
+
 #endif /* _STRINGLIST_H */
diff --git a/headers/compatibility/bsd/sys/cdefs.h b/headers/compatibility/bsd/sys/cdefs.h
index f82b7d747a..6647d2e90e 100644
--- a/headers/compatibility/bsd/sys/cdefs.h
+++ b/headers/compatibility/bsd/sys/cdefs.h
@@ -9,10 +9,17 @@
 #include_next <sys/cdefs.h>
 
 
+#ifdef _BSD_SOURCE
+
+
 #define __FBSDID(x)
 #define __unused
 
 #define __printflike(a, b)	__attribute__ ((format (__printf__, (a), (b))))
 #define __printf0like(a, b)
 
+
+#endif
+
+
 #endif	/* _BSD_SYS_CDEFS_H_ */
diff --git a/headers/compatibility/bsd/sys/ioccom.h b/headers/compatibility/bsd/sys/ioccom.h
index 9af5c74643..ea9583cad4 100644
--- a/headers/compatibility/bsd/sys/ioccom.h
+++ b/headers/compatibility/bsd/sys/ioccom.h
@@ -6,6 +6,10 @@
 #ifndef _SYS_IOCCOM_H
 #define _SYS_IOCCOM_H
 
+
+#ifdef _BSD_SOURCE
+
+
 /**
  * @defgroup IOCTL_common sys/ioccom.h
  * @brief Definitions & maros common to ioctl()
@@ -77,4 +81,8 @@
 
 /** @} */
 
+
+#endif
+
+
 #endif /* _SYS_IOCCOM_H */
diff --git a/headers/compatibility/bsd/sys/md4.h b/headers/compatibility/bsd/sys/md4.h
index 21e6c94a1f..07992e9cea 100644
--- a/headers/compatibility/bsd/sys/md4.h
+++ b/headers/compatibility/bsd/sys/md4.h
@@ -26,6 +26,11 @@
 
 #ifndef _MD4_H_
 #define _MD4_H_
+
+
+#ifdef _BSD_SOURCE
+
+
 /* MD4 context. */
 typedef struct MD4Context {
   u_int32_t state[4];	/* state (ABCD) */
@@ -45,4 +50,8 @@ char * MD4File(const char *, char *);
 char * MD4Data(const unsigned char *, unsigned int, char *);
 __END_DECLS
 
+
+#endif
+
+
 #endif /* _MD4_H_ */
diff --git a/headers/compatibility/bsd/sys/md5.h b/headers/compatibility/bsd/sys/md5.h
index b0e912362e..6f077b4f32 100644
--- a/headers/compatibility/bsd/sys/md5.h
+++ b/headers/compatibility/bsd/sys/md5.h
@@ -28,6 +28,10 @@ documentation and/or software.
 #ifndef _SYS_MD5_H_
 #define _SYS_MD5_H_
 
+
+#ifdef _BSD_SOURCE
+
+
 #include <stdint.h>
 
 #define MD5_BLOCK_LENGTH		64
@@ -52,4 +56,9 @@ char * MD5File(const char *, char *);
 char * MD5FileChunk(const char *, char *, off_t, off_t);
 char * MD5Data(const unsigned char *, unsigned int, char *);
 __END_DECLS
+
+
+#endif
+
+
 #endif /* _SYS_MD5_H_ */
diff --git a/headers/compatibility/bsd/sys/param.h b/headers/compatibility/bsd/sys/param.h
index 3f86391340..d76da9bd44 100644
--- a/headers/compatibility/bsd/sys/param.h
+++ b/headers/compatibility/bsd/sys/param.h
@@ -9,6 +9,9 @@
 #include_next <sys/param.h>
 
 
+#ifdef _BSD_SOURCE
+
+
 #ifndef _ALIGNBYTES
 #	define _ALIGNBYTES 7
 #endif
@@ -31,4 +34,8 @@
 #	define MAXLOGNAME 32
 #endif
 
+
+#endif
+
+
 #endif	/* _BSD_SYS_PARAM_H_ */
diff --git a/headers/compatibility/bsd/sys/wait.h b/headers/compatibility/bsd/sys/wait.h
index b13a4399c3..567f2b3d6d 100644
--- a/headers/compatibility/bsd/sys/wait.h
+++ b/headers/compatibility/bsd/sys/wait.h
@@ -8,6 +8,10 @@
 
 #include_next <sys/wait.h>
 
+
+#ifdef _BSD_SOURCE
+
+
 #include <sys/resource.h>
 
 
@@ -23,4 +27,8 @@ pid_t wait4(pid_t pid, int *status, int options, struct rusage *rusage);
 }
 #endif
 
+
+#endif
+
+
 #endif	/* _BSD_SYS_WAIT_H_ */
diff --git a/headers/compatibility/bsd/sysexits.h b/headers/compatibility/bsd/sysexits.h
index e52bb5be95..a6b34473f1 100644
--- a/headers/compatibility/bsd/sysexits.h
+++ b/headers/compatibility/bsd/sysexits.h
@@ -34,6 +34,10 @@
 #ifndef	_SYSEXITS_H_
 #define	_SYSEXITS_H_
 
+
+#ifdef _BSD_SOURCE
+
+
 /*
  *  SYSEXITS.H -- Exit status codes for system programs.
  *
@@ -113,4 +117,8 @@
 
 #define EX__MAX	78	/* maximum listed value */
 
+
+#endif
+
+
 #endif /* !_SYSEXITS_H_ */
diff --git a/headers/compatibility/bsd/time.h b/headers/compatibility/bsd/time.h
index 6628490855..ff0fb0ec7b 100644
--- a/headers/compatibility/bsd/time.h
+++ b/headers/compatibility/bsd/time.h
@@ -9,6 +9,9 @@
 #include_next <time.h>
 
 
+#ifdef _BSD_SOURCE
+
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -20,4 +23,8 @@ time_t	timegm(struct tm *tm);
 }
 #endif
 
+
+#endif
+
+
 #endif	/* _BSD_TIME_H_ */
diff --git a/headers/compatibility/bsd/unistd.h b/headers/compatibility/bsd/unistd.h
index 65320b244f..fbcd17cce1 100644
--- a/headers/compatibility/bsd/unistd.h
+++ b/headers/compatibility/bsd/unistd.h
@@ -9,6 +9,9 @@
 #include_next <unistd.h>
 
 
+#ifdef _BSD_SOURCE
+
+
 #define L_SET	SEEK_SET
 #define	L_INCR	SEEK_CUR
 #define	L_XTND	SEEK_END
@@ -28,4 +31,8 @@ void	setusershell(void);
 }
 #endif
 
+
+#endif
+
+
 #endif	/* _BSD_UNISTD_H_ */
diff --git a/headers/compatibility/bsd/vis.h b/headers/compatibility/bsd/vis.h
index 5e64de30da..68b90cc97b 100644
--- a/headers/compatibility/bsd/vis.h
+++ b/headers/compatibility/bsd/vis.h
@@ -38,6 +38,9 @@
 #define	_VIS_H_
 
 
+#ifdef _BSD_SOURCE
+
+
 #include <sys/types.h>
 
 
@@ -89,4 +92,8 @@ int	strunvisx(char *, const char *, int);
 int	unvis(char *, int, int *, int);
 __END_DECLS
 
+
+#endif
+
+
 #endif /* !_VIS_H_ */
diff --git a/src/add-ons/kernel/bus_managers/firewire/Jamfile b/src/add-ons/kernel/bus_managers/firewire/Jamfile
index e33b186f43..7151a9f36f 100644
--- a/src/add-ons/kernel/bus_managers/firewire/Jamfile
+++ b/src/add-ons/kernel/bus_managers/firewire/Jamfile
@@ -4,7 +4,9 @@ UseHeaders [ FDirName $(HAIKU_TOP) headers compatibility bsd ] : true ;
 UsePrivateHeaders firewire ;
 UsePrivateKernelHeaders ;
 
-DEFINES += _KERNEL=1 ;
+local defines = [ FDefines _KERNEL=1 _BSD_SOURCE=1 ] ;
+SubDirCcFlags $(defines) ;
+SubDirC++Flags $(defines) ;
 
 KernelAddon firewire :
 	util.c
diff --git a/src/add-ons/kernel/drivers/bus/firewire/Jamfile b/src/add-ons/kernel/drivers/bus/firewire/Jamfile
index f9ed678999..fd456f583d 100644
--- a/src/add-ons/kernel/drivers/bus/firewire/Jamfile
+++ b/src/add-ons/kernel/drivers/bus/firewire/Jamfile
@@ -4,7 +4,7 @@ UseHeaders [ FDirName $(HAIKU_TOP) headers compatibility bsd ] : true ;
 UsePrivateHeaders firewire ;
 UsePrivateKernelHeaders ;
 
-SubDirCcFlags [ FDefines _KERNEL=1 ] ;
+SubDirCcFlags [ FDefines _KERNEL=1 _BSD_SOURCE=1 ] ;
 
 KernelAddon fw_raw :
 	fw_raw.c
diff --git a/src/add-ons/media/media-add-ons/firewire_dv/Jamfile b/src/add-ons/media/media-add-ons/firewire_dv/Jamfile
index 8695fa29ea..5fcba34523 100644
--- a/src/add-ons/media/media-add-ons/firewire_dv/Jamfile
+++ b/src/add-ons/media/media-add-ons/firewire_dv/Jamfile
@@ -5,6 +5,7 @@ UseHeaders [ FDirName $(HAIKU_TOP) headers compatibility bsd ] : true ;
 UsePrivateHeaders firewire ;
 UsePrivateHeaders media ;
 UsePrivateHeaders shared ;
+SubDirC++Flags [ FDefines _BSD_SOURCE=1 ] ;
 
 local architectureObject ;
 for architectureObject in [ MultiArchSubDirSetup ] {
diff --git a/src/apps/debugger/Jamfile b/src/apps/debugger/Jamfile
index a265e56f92..d344ee3875 100644
--- a/src/apps/debugger/Jamfile
+++ b/src/apps/debugger/Jamfile
@@ -11,6 +11,8 @@ UsePrivateSystemHeaders ;
 
 LINKFLAGS += -Wl,--exclude-libs,ALL ;
 
+SubDirC++Flags [ FDefines _BSD_SOURCE=1 ] ;
+
 SEARCH_SOURCE += [ FDirName $(SUBDIR) arch ] ;
 SEARCH_SOURCE += [ FDirName $(SUBDIR) arch x86 ] ;
 SEARCH_SOURCE += [ FDirName $(SUBDIR) arch x86_64 ] ;
diff --git a/src/bin/fwcontrol/Jamfile b/src/bin/fwcontrol/Jamfile
index 3c133212ab..9cf8bda467 100644
--- a/src/bin/fwcontrol/Jamfile
+++ b/src/bin/fwcontrol/Jamfile
@@ -2,6 +2,7 @@ SubDir HAIKU_TOP src bin fwcontrol ;
 
 UseHeaders [ FDirName $(HAIKU_TOP) headers compatibility bsd ] : true ;
 UsePrivateHeaders firewire ;
+SubDirCcFlags [ FDefines _BSD_SOURCE=1 ] ;
 
 BinCommand fwcontrol :
 	eui64.c
diff --git a/src/bin/network/ftp/Jamfile b/src/bin/network/ftp/Jamfile
index b21487fc04..03df6062c9 100644
--- a/src/bin/network/ftp/Jamfile
+++ b/src/bin/network/ftp/Jamfile
@@ -9,6 +9,7 @@ if ! $(TARGET_PLATFORM_HAIKU_COMPATIBLE) {
 }
 
 UseHeaders [ FDirName $(HAIKU_TOP) headers compatibility bsd ] : true ;
+SubDirCcFlags [ FDefines _BSD_SOURCE=1 ] ;
 
 BinCommand ftp :
 	cmds.c
diff --git a/src/bin/network/ftpd/Jamfile b/src/bin/network/ftpd/Jamfile
index f87b6576e8..0b09a85d9f 100644
--- a/src/bin/network/ftpd/Jamfile
+++ b/src/bin/network/ftpd/Jamfile
@@ -10,6 +10,7 @@ if ! $(TARGET_PLATFORM_HAIKU_COMPATIBLE) {
 
 UseHeaders [ FDirName $(HAIKU_TOP) headers compatibility bsd ] : true ;
 UseHeaders $(SUBDIR) : true ;
+SubDirCcFlags [ FDefines _BSD_SOURCE=1 ] ;
 
 BinCommand ftpd :
 	ftpd.c
diff --git a/src/bin/network/tcpdump/Jamfile b/src/bin/network/tcpdump/Jamfile
index 6fb6008a8c..1360192107 100644
--- a/src/bin/network/tcpdump/Jamfile
+++ b/src/bin/network/tcpdump/Jamfile
@@ -4,7 +4,8 @@ UseHeaders [ FDirName $(HAIKU_TOP) headers compatibility bsd ] : true ;
 UseHeaders [ FDirName $(SUBDIR) ] : true ;
 UseHeaders [ FDirName $(SUBDIR) libpcap ] : true ;
 
-local defines = [ FDefines HAVE_CONFIG_H=1 _U_=\"__attribute__((unused))\" INET6=1 HAVE_SOCKADDR_STORAGE=1 ] ;
+local defines = [ FDefines HAVE_CONFIG_H=1 _U_=\"__attribute__((unused))\"
+	INET6=1 HAVE_SOCKADDR_STORAGE=1 _BSD_SOURCE=1 ] ;
 
 SubDirCcFlags $(defines) ;
 SubDirC++Flags $(defines) ;
diff --git a/src/bin/network/telnet/Jamfile b/src/bin/network/telnet/Jamfile
index c1a31fd514..d8fb20a6cf 100644
--- a/src/bin/network/telnet/Jamfile
+++ b/src/bin/network/telnet/Jamfile
@@ -6,7 +6,7 @@ UseHeaders [ FDirName $(HAIKU_TOP) src libs libtelnet ] : false ;
 
 UseBuildFeatureHeaders ncurses ;
 
-local defines = [ FDefines USE_TERMIO=1 OLD_ENVIRON=1 ENV_HACK=1 ] ;
+local defines = [ FDefines USE_TERMIO=1 OLD_ENVIRON=1 ENV_HACK=1 _BSD_SOURCE=1 ] ;
 
 SubDirCcFlags $(defines) ;
 SubDirC++Flags $(defines) ;
diff --git a/src/bin/network/telnetd/Jamfile b/src/bin/network/telnetd/Jamfile
index 2faf3facac..1581c7d54f 100644
--- a/src/bin/network/telnetd/Jamfile
+++ b/src/bin/network/telnetd/Jamfile
@@ -5,7 +5,7 @@ UseHeaders [ FDirName $(HAIKU_TOP) headers compatibility bsd ] : true ;
 UseHeaders [ FDirName $(HAIKU_TOP) src libs ] : true ;
 UseHeaders [ FDirName $(HAIKU_TOP) src libs libtelnet ] : false ;
 
-local defines = [ FDefines USE_TERMIO=1 ] ;
+local defines = [ FDefines USE_TERMIO=1 _BSD_SOURCE=1 ] ;
 
 SubDirCcFlags $(defines) ;
 SubDirC++Flags $(defines) ;
diff --git a/src/kits/network/libnetapi/Jamfile b/src/kits/network/libnetapi/Jamfile
index 34b3eae24e..c0039e215a 100644
--- a/src/kits/network/libnetapi/Jamfile
+++ b/src/kits/network/libnetapi/Jamfile
@@ -9,6 +9,8 @@ UseHeaders [ FDirName $(HAIKU_TOP) src libs compat freebsd_wlan ] : true ;
 UseHeaders [ FDirName $(HAIKU_TOP) headers os add-ons network_settings ]
 	: true ;
 
+SubDirC++Flags [ FDefines _BSD_SOURCE=1 ] ;
+
 local architectureObject ;
 for architectureObject in [ MultiArchSubDirSetup ] {
 	on $(architectureObject) {
diff --git a/src/libs/bsd/Jamfile b/src/libs/bsd/Jamfile
index eae0800511..948eadc73c 100644
--- a/src/libs/bsd/Jamfile
+++ b/src/libs/bsd/Jamfile
@@ -4,6 +4,8 @@ SetSubDirSupportedPlatforms $(HAIKU_BONE_COMPATIBLE_PLATFORMS) ;
 
 UseHeaders [ FDirName $(HAIKU_TOP) headers compatibility bsd ] : true ;
 
+SubDirC++Flags [ FDefines _BSD_SOURCE=1 ] ;
+
 local architectureObject ;
 for architectureObject in [ MultiArchSubDirSetup ] {
 	on $(architectureObject) {
diff --git a/src/libs/edit/Jamfile b/src/libs/edit/Jamfile
index 7f70af8624..779441a3e5 100644
--- a/src/libs/edit/Jamfile
+++ b/src/libs/edit/Jamfile
@@ -5,7 +5,7 @@ SetSubDirSupportedPlatforms $(HAIKU_BONE_COMPATIBLE_PLATFORMS) ;
 UseBuildFeatureHeaders ncurses ;
 UseHeaders [ FDirName $(HAIKU_TOP) headers compatibility bsd ] : true ;
 
-local defines = [ FDefines SCCSID=0 ] ;
+local defines = [ FDefines SCCSID=0 _BSD_SOURCE=1 ] ;
 SubDirCcFlags $(defines) ;
 
 local sources =
diff --git a/src/libs/libtelnet/Jamfile b/src/libs/libtelnet/Jamfile
index fdd0300ae7..beb0083304 100644
--- a/src/libs/libtelnet/Jamfile
+++ b/src/libs/libtelnet/Jamfile
@@ -3,6 +3,7 @@ SubDir HAIKU_TOP src libs libtelnet ;
 SetSubDirSupportedPlatforms $(HAIKU_BONE_COMPATIBLE_PLATFORMS) ;
 
 UseHeaders [ FDirName $(HAIKU_TOP) headers compatibility bsd ] : true ;
+SubDirCcFlags [ FDefines _BSD_SOURCE=1 ] ;
 
 StaticLibrary libtelnet.a :
 	auth.c
diff --git a/src/libs/util/Jamfile b/src/libs/util/Jamfile
index 78712840db..a497db85f1 100644
--- a/src/libs/util/Jamfile
+++ b/src/libs/util/Jamfile
@@ -4,7 +4,7 @@ SetSubDirSupportedPlatforms $(HAIKU_BONE_COMPATIBLE_PLATFORMS) ;
 
 UseHeaders [ FDirName $(HAIKU_TOP) headers compatibility bsd ] : true ;
 
-local defines = [ FDefines SCCSID=0 ] ;
+local defines = [ FDefines SCCSID=0 _BSD_SOURCE=1 ] ;
 SubDirCcFlags $(defines) ;
 
 StaticLibrary libutil.a :