diff --git a/libc/include/sys/auxv.h b/libc/include/sys/auxv.h
index 0d753c3..4611fcc 100644
--- a/libc/include/sys/auxv.h
+++ b/libc/include/sys/auxv.h
@@ -33,7 +33,7 @@
 
 __BEGIN_DECLS
 
-unsigned long int getauxval(unsigned long int type);
+unsigned long int getauxval(unsigned long int type) __INTRODUCED_IN(21);
 
 __END_DECLS
 
diff --git a/libc/include/sys/endian.h b/libc/include/sys/endian.h
index 60cc030..449e0d7 100644
--- a/libc/include/sys/endian.h
+++ b/libc/include/sys/endian.h
@@ -49,10 +49,10 @@
 
 /* glibc compatibility. */
 __BEGIN_DECLS
-uint32_t htonl(uint32_t) __pure2;
-uint16_t htons(uint16_t) __pure2;
-uint32_t ntohl(uint32_t) __pure2;
-uint16_t ntohs(uint16_t) __pure2;
+uint32_t htonl(uint32_t) __pure2 __INTRODUCED_IN(21);
+uint16_t htons(uint16_t) __pure2 __INTRODUCED_IN(21);
+uint32_t ntohl(uint32_t) __pure2 __INTRODUCED_IN(21);
+uint16_t ntohs(uint16_t) __pure2 __INTRODUCED_IN(21);
 __END_DECLS
 
 #define htonl(x) __swap32(x)
diff --git a/libc/include/sys/epoll.h b/libc/include/sys/epoll.h
index 4a5a37c..4ec8969 100644
--- a/libc/include/sys/epoll.h
+++ b/libc/include/sys/epoll.h
@@ -74,10 +74,10 @@
 ;
 
 int epoll_create(int);
-int epoll_create1(int);
+int epoll_create1(int) __INTRODUCED_IN(21);
 int epoll_ctl(int, int, int, struct epoll_event*);
 int epoll_wait(int, struct epoll_event*, int, int);
-int epoll_pwait(int, struct epoll_event*, int, int, const sigset_t*);
+int epoll_pwait(int, struct epoll_event*, int, int, const sigset_t*) __INTRODUCED_IN(21);
 
 __END_DECLS
 
diff --git a/libc/include/sys/fsuid.h b/libc/include/sys/fsuid.h
index 03355b7..223db90 100644
--- a/libc/include/sys/fsuid.h
+++ b/libc/include/sys/fsuid.h
@@ -34,8 +34,8 @@
 
 __BEGIN_DECLS
 
-extern int setfsuid(uid_t);
-extern int setfsgid(gid_t);
+extern int setfsuid(uid_t) __INTRODUCED_IN(21);
+extern int setfsgid(gid_t) __INTRODUCED_IN(21);
 
 __END_DECLS
 
diff --git a/libc/include/sys/inotify.h b/libc/include/sys/inotify.h
index dcdd29a..dcf0e1d 100644
--- a/libc/include/sys/inotify.h
+++ b/libc/include/sys/inotify.h
@@ -41,7 +41,7 @@
 #define IN_NONBLOCK O_NONBLOCK
 
 extern int inotify_init(void);
-extern int inotify_init1(int);
+extern int inotify_init1(int) __INTRODUCED_IN(21);
 extern int inotify_add_watch(int, const char*, uint32_t);
 extern int inotify_rm_watch(int, uint32_t);
 
diff --git a/libc/include/sys/mman.h b/libc/include/sys/mman.h
index 170300a..af96eff 100644
--- a/libc/include/sys/mman.h
+++ b/libc/include/sys/mman.h
@@ -50,26 +50,26 @@
 #define POSIX_MADV_DONTNEED   MADV_DONTNEED
 
 #if defined(__USE_FILE_OFFSET64)
-extern void* mmap(void*, size_t, int, int, int, off_t) __RENAME(mmap64);
+extern void* mmap(void*, size_t, int, int, int, off_t) __RENAME(mmap64) __INTRODUCED_IN(21);
 #else
 extern void* mmap(void*, size_t, int, int, int, off_t);
 #endif
-extern void* mmap64(void*, size_t, int, int, int, off64_t);
+extern void* mmap64(void*, size_t, int, int, int, off64_t) __INTRODUCED_IN(21);
 
 extern int munmap(void*, size_t);
 extern int msync(const void*, size_t, int);
 extern int mprotect(const void*, size_t, int);
 extern void* mremap(void*, size_t, size_t, int, ...);
 
-extern int mlockall(int);
-extern int munlockall(void);
+extern int mlockall(int) __INTRODUCED_IN(21);
+extern int munlockall(void) __INTRODUCED_IN(21);
 extern int mlock(const void*, size_t);
 extern int munlock(const void*, size_t);
 
 extern int mincore(void*, size_t, unsigned char*);
 
 extern int madvise(void*, size_t, int);
-extern int posix_madvise(void*, size_t, int);
+extern int posix_madvise(void*, size_t, int) __INTRODUCED_IN(23);
 
 __END_DECLS
 
diff --git a/libc/include/sys/personality.h b/libc/include/sys/personality.h
index 7764468..68ae77c 100644
--- a/libc/include/sys/personality.h
+++ b/libc/include/sys/personality.h
@@ -34,7 +34,7 @@
 
 __BEGIN_DECLS
 
-extern int personality (unsigned int persona);
+extern int personality(unsigned int persona) __INTRODUCED_IN(21);
 
 __END_DECLS
 
diff --git a/libc/include/sys/quota.h b/libc/include/sys/quota.h
index f4f6447..85bb780 100644
--- a/libc/include/sys/quota.h
+++ b/libc/include/sys/quota.h
@@ -40,7 +40,7 @@
 
 __BEGIN_DECLS
 
-int quotactl(int, const char*, int, char*);
+int quotactl(int, const char*, int, char*) __INTRODUCED_IN(25);
 
 __END_DECLS
 
diff --git a/libc/include/sys/resource.h b/libc/include/sys/resource.h
index 8209dfb..74e903f 100644
--- a/libc/include/sys/resource.h
+++ b/libc/include/sys/resource.h
@@ -45,16 +45,16 @@
 extern int getrlimit(int, struct rlimit*);
 extern int setrlimit(int, const struct rlimit*);
 
-extern int getrlimit64(int, struct rlimit64*);
-extern int setrlimit64(int, const struct rlimit64*);
+extern int getrlimit64(int, struct rlimit64*) __INTRODUCED_IN(21);
+extern int setrlimit64(int, const struct rlimit64*) __INTRODUCED_IN(21);
 
 extern int getpriority(int, int);
 extern int setpriority(int, int, int);
 
 extern int getrusage(int, struct rusage*);
 
-extern int prlimit(pid_t, int, const struct rlimit*, struct rlimit*);
-extern int prlimit64(pid_t, int, const struct rlimit64*, struct rlimit64*);
+extern int prlimit(pid_t, int, const struct rlimit*, struct rlimit*) __INTRODUCED_IN(24);
+extern int prlimit64(pid_t, int, const struct rlimit64*, struct rlimit64*) __INTRODUCED_IN(21);
 
 __END_DECLS
 
diff --git a/libc/include/sys/select.h b/libc/include/sys/select.h
index 0c4a823..06c1c72 100644
--- a/libc/include/sys/select.h
+++ b/libc/include/sys/select.h
@@ -57,9 +57,9 @@
     } \
   } while (0)
 
-extern void __FD_CLR_chk(int, fd_set*, size_t);
-extern void __FD_SET_chk(int, fd_set*, size_t);
-extern int  __FD_ISSET_chk(int, fd_set*, size_t);
+extern void __FD_CLR_chk(int, fd_set*, size_t) __INTRODUCED_IN(21);
+extern void __FD_SET_chk(int, fd_set*, size_t) __INTRODUCED_IN(21);
+extern int __FD_ISSET_chk(int, fd_set*, size_t) __INTRODUCED_IN(21);
 
 #if defined(__BIONIC_FORTIFY)
 #define FD_CLR(fd, set) __FD_CLR_chk(fd, set, __bos(set))
diff --git a/libc/include/sys/sendfile.h b/libc/include/sys/sendfile.h
index c588e68..f90498a 100644
--- a/libc/include/sys/sendfile.h
+++ b/libc/include/sys/sendfile.h
@@ -35,11 +35,12 @@
 __BEGIN_DECLS
 
 #if defined(__USE_FILE_OFFSET64)
-extern ssize_t sendfile(int out_fd, int in_fd, off_t* offset, size_t count) __RENAME(sendfile64);
+extern ssize_t sendfile(int out_fd, int in_fd, off_t* offset, size_t count) __RENAME(sendfile64)
+  __INTRODUCED_IN(21);
 #else
 extern ssize_t sendfile(int out_fd, int in_fd, off_t* offset, size_t count);
 #endif
-extern ssize_t sendfile64(int out_fd, int in_fd, off64_t* offset, size_t count);
+extern ssize_t sendfile64(int out_fd, int in_fd, off64_t* offset, size_t count) __INTRODUCED_IN(21);
 
 __END_DECLS
 
diff --git a/libc/include/sys/signalfd.h b/libc/include/sys/signalfd.h
index 2537ab9..5b67822 100644
--- a/libc/include/sys/signalfd.h
+++ b/libc/include/sys/signalfd.h
@@ -35,7 +35,7 @@
 
 __BEGIN_DECLS
 
-extern int signalfd(int fd, const sigset_t* mask, int flags) __nonnull((2));
+extern int signalfd(int fd, const sigset_t* mask, int flags) __nonnull((2)) __INTRODUCED_IN(21);
 
 __END_DECLS
 
diff --git a/libc/include/sys/socket.h b/libc/include/sys/socket.h
index c7e9acc..85999f3 100644
--- a/libc/include/sys/socket.h
+++ b/libc/include/sys/socket.h
@@ -113,7 +113,7 @@
    ? (struct cmsghdr*) (msg)->msg_control : (struct cmsghdr*) NULL)
 #define CMSG_OK(mhdr, cmsg) ((cmsg)->cmsg_len >= sizeof(struct cmsghdr) &&   (cmsg)->cmsg_len <= (unsigned long)   ((mhdr)->msg_controllen -   ((char*)(cmsg) - (char*)(mhdr)->msg_control)))
 
-struct cmsghdr* __cmsg_nxthdr(struct msghdr*, struct cmsghdr*);
+struct cmsghdr* __cmsg_nxthdr(struct msghdr*, struct cmsghdr*) __INTRODUCED_IN(21);
 
 #define SCM_RIGHTS 0x01
 #define SCM_CREDENTIALS 0x02
@@ -269,16 +269,17 @@
 #endif
 
 __socketcall int accept(int, struct sockaddr*, socklen_t*);
-__socketcall int accept4(int, struct sockaddr*, socklen_t*, int);
+__socketcall int accept4(int, struct sockaddr*, socklen_t*, int) __INTRODUCED_IN(21);
 __socketcall int bind(int, const struct sockaddr*, int);
 __socketcall int connect(int, const struct sockaddr*, socklen_t);
 __socketcall int getpeername(int, struct sockaddr*, socklen_t*);
 __socketcall int getsockname(int, struct sockaddr*, socklen_t*);
 __socketcall int getsockopt(int, int, int, void*, socklen_t*);
 __socketcall int listen(int, int);
-__socketcall int recvmmsg(int, struct mmsghdr*, unsigned int, int, const struct timespec*);
+__socketcall int recvmmsg(int, struct mmsghdr*, unsigned int, int, const struct timespec*)
+  __INTRODUCED_IN(21);
 __socketcall int recvmsg(int, struct msghdr*, int);
-__socketcall int sendmmsg(int, const struct mmsghdr*, unsigned int, int);
+__socketcall int sendmmsg(int, const struct mmsghdr*, unsigned int, int) __INTRODUCED_IN(21);
 __socketcall int sendmsg(int, const struct msghdr*, int);
 __socketcall int setsockopt(int, int, int, const void*, socklen_t);
 __socketcall int shutdown(int, int);
@@ -292,7 +293,8 @@
 __socketcall ssize_t recvfrom(int, void*, size_t, int, const struct sockaddr*, socklen_t*);
 
 __errordecl(__recvfrom_error, "recvfrom called with size bigger than buffer");
-extern ssize_t __recvfrom_chk(int, void*, size_t, size_t, int, const struct sockaddr*, socklen_t*);
+extern ssize_t __recvfrom_chk(int, void*, size_t, size_t, int, const struct sockaddr*, socklen_t*)
+  __INTRODUCED_IN(21);
 extern ssize_t __recvfrom_real(int, void*, size_t, int, const struct sockaddr*, socklen_t*) __RENAME(recvfrom);
 
 #if defined(__BIONIC_FORTIFY)
diff --git a/libc/include/sys/stat.h b/libc/include/sys/stat.h
index ae85f62..46eec96 100644
--- a/libc/include/sys/stat.h
+++ b/libc/include/sys/stat.h
@@ -146,18 +146,18 @@
 extern int mkdir(const char*, mode_t);
 
 extern int fstat(int, struct stat*);
-extern int fstat64(int, struct stat64*);
+extern int fstat64(int, struct stat64*) __INTRODUCED_IN(21);
 extern int fstatat(int, const char*, struct stat*, int);
-extern int fstatat64(int, const char*, struct stat64*, int);
+extern int fstatat64(int, const char*, struct stat64*, int) __INTRODUCED_IN(21);
 extern int lstat(const char*, struct stat*);
-extern int lstat64(const char*, struct stat64*);
+extern int lstat64(const char*, struct stat64*) __INTRODUCED_IN(21);
 extern int stat(const char*, struct stat*);
-extern int stat64(const char*, struct stat64*);
+extern int stat64(const char*, struct stat64*) __INTRODUCED_IN(21);
 
 extern int mknod(const char*, mode_t, dev_t);
 extern mode_t umask(mode_t);
 
-extern mode_t __umask_chk(mode_t);
+extern mode_t __umask_chk(mode_t) __INTRODUCED_IN(21);
 extern mode_t __umask_real(mode_t) __RENAME(umask);
 __errordecl(__umask_invalid_mode, "umask called with invalid mode");
 
@@ -178,16 +178,17 @@
 #endif /* defined(__BIONIC_FORTIFY) */
 
 __BIONIC_LEGACY_INLINE int mkfifo(const char*, mode_t);
-extern int mkfifoat(int, const char*, mode_t);
+extern int mkfifoat(int, const char*, mode_t) __INTRODUCED_IN(23);
 
 extern int fchmodat(int, const char*, mode_t, int);
 extern int mkdirat(int, const char*, mode_t);
-extern int mknodat(int, const char*, mode_t, dev_t);
+extern int mknodat(int, const char*, mode_t, dev_t) __INTRODUCED_IN(21);
 
 #define UTIME_NOW  ((1L << 30) - 1L)
 #define UTIME_OMIT ((1L << 30) - 2L)
-extern int utimensat(int fd, const char *path, const struct timespec times[2], int flags);
-extern int futimens(int fd, const struct timespec times[2]);
+extern int utimensat(int fd, const char* path, const struct timespec times[2], int flags)
+  __INTRODUCED_IN(12);
+extern int futimens(int fd, const struct timespec times[2]) __INTRODUCED_IN(19);
 
 __END_DECLS
 
diff --git a/libc/include/sys/statvfs.h b/libc/include/sys/statvfs.h
index 3495546..e12f069 100644
--- a/libc/include/sys/statvfs.h
+++ b/libc/include/sys/statvfs.h
@@ -59,10 +59,12 @@
 #define ST_NODIRATIME  0x0800
 #define ST_RELATIME    0x1000
 
-extern int statvfs(const char* __restrict, struct statvfs* __restrict) __nonnull((1, 2));
-extern int statvfs64(const char* __restrict, struct statvfs64* __restrict) __nonnull((1, 2));
-extern int fstatvfs(int, struct statvfs*) __nonnull((2));
-extern int fstatvfs64(int, struct statvfs64*) __nonnull((2));
+extern int statvfs(const char* __restrict, struct statvfs* __restrict) __nonnull((1, 2))
+  __INTRODUCED_IN(21);
+extern int statvfs64(const char* __restrict, struct statvfs64* __restrict) __nonnull((1, 2))
+  __INTRODUCED_IN(21);
+extern int fstatvfs(int, struct statvfs*) __nonnull((2)) __INTRODUCED_IN(21);
+extern int fstatvfs64(int, struct statvfs64*) __nonnull((2)) __INTRODUCED_IN(21);
 
 __END_DECLS
 
diff --git a/libc/include/sys/swap.h b/libc/include/sys/swap.h
index e4c1819..b1f9295 100644
--- a/libc/include/sys/swap.h
+++ b/libc/include/sys/swap.h
@@ -38,8 +38,8 @@
 #define SWAP_FLAG_PRIO_MASK 0x7fff
 #define SWAP_FLAG_PRIO_SHIFT 0
 
-extern int swapon(const char*, int) __nonnull((1));
-extern int swapoff(const char*) __nonnull((1));
+extern int swapon(const char*, int) __nonnull((1)) __INTRODUCED_IN(21);
+extern int swapoff(const char*) __nonnull((1)) __INTRODUCED_IN(21);
 
 __END_DECLS
 
diff --git a/libc/include/sys/sysinfo.h b/libc/include/sys/sysinfo.h
index b66bc8e..9a10d64 100644
--- a/libc/include/sys/sysinfo.h
+++ b/libc/include/sys/sysinfo.h
@@ -35,13 +35,13 @@
 
 int sysinfo(struct sysinfo* info);
 
-int get_nprocs_conf(void);
+int get_nprocs_conf(void) __INTRODUCED_IN(23);
 
-int get_nprocs(void);
+int get_nprocs(void) __INTRODUCED_IN(23);
 
-long get_phys_pages(void);
+long get_phys_pages(void) __INTRODUCED_IN(23);
 
-long get_avphys_pages(void);
+long get_avphys_pages(void) __INTRODUCED_IN(23);
 
 __END_DECLS
 
diff --git a/libc/include/sys/system_properties.h b/libc/include/sys/system_properties.h
index 01c3db3..99a6e59 100644
--- a/libc/include/sys/system_properties.h
+++ b/libc/include/sys/system_properties.h
@@ -48,7 +48,7 @@
 
 /* Set a system property by name.
 **/
-int __system_property_set(const char *key, const char *value);
+int __system_property_set(const char* key, const char* value) __INTRODUCED_IN(21);
 
 /* Return a pointer to the system property named name, if it
 ** exists, or NULL if there is no such property.  Use 
@@ -93,9 +93,8 @@
 ** Order of results may change from call to call.  This is
 ** not a bug.
 */
-int __system_property_foreach(
-        void (*propfn)(const prop_info *pi, void *cookie),
-        void *cookie);
+int __system_property_foreach(void (*propfn)(const prop_info* pi, void* cookie), void* cookie)
+  __INTRODUCED_IN(21);
 
 __END_DECLS
 
diff --git a/libc/include/sys/timerfd.h b/libc/include/sys/timerfd.h
index 1aa97b4..a189742 100644
--- a/libc/include/sys/timerfd.h
+++ b/libc/include/sys/timerfd.h
@@ -41,10 +41,10 @@
 #define TFD_CLOEXEC O_CLOEXEC
 #define TFD_NONBLOCK O_NONBLOCK
 
-extern int timerfd_create(clockid_t, int);
-extern int timerfd_settime(int, int, const struct itimerspec*,
-                           struct itimerspec*);
-extern int timerfd_gettime(int, struct itimerspec*);
+extern int timerfd_create(clockid_t, int) __INTRODUCED_IN(21);
+extern int timerfd_settime(int, int, const struct itimerspec*, struct itimerspec*)
+  __INTRODUCED_IN(21);
+extern int timerfd_gettime(int, struct itimerspec*) __INTRODUCED_IN(21);
 
 __END_DECLS
 
diff --git a/libc/include/sys/timex.h b/libc/include/sys/timex.h
index fade5c3..f704ce8 100644
--- a/libc/include/sys/timex.h
+++ b/libc/include/sys/timex.h
@@ -35,8 +35,8 @@
 
 __BEGIN_DECLS
 
-int adjtimex(struct timex*);
-int clock_adjtime(clockid_t, struct timex*);
+int adjtimex(struct timex*) __INTRODUCED_IN(24);
+int clock_adjtime(clockid_t, struct timex*) __INTRODUCED_IN(24);
 
 __END_DECLS
 
diff --git a/libc/include/sys/uio.h b/libc/include/sys/uio.h
index 72675d1..7a009b4 100644
--- a/libc/include/sys/uio.h
+++ b/libc/include/sys/uio.h
@@ -42,16 +42,18 @@
 ssize_t preadv(int, const struct iovec*, int, off_t) __RENAME(preadv64);
 ssize_t pwritev(int, const struct iovec*, int, off_t) __RENAME(pwritev64);
 #else
-ssize_t preadv(int, const struct iovec*, int, off_t);
-ssize_t pwritev(int, const struct iovec*, int, off_t);
+ssize_t preadv(int, const struct iovec*, int, off_t) __INTRODUCED_IN(24);
+ssize_t pwritev(int, const struct iovec*, int, off_t) __INTRODUCED_IN(24);
 #endif
-ssize_t preadv64(int, const struct iovec*, int, off64_t);
-ssize_t pwritev64(int, const struct iovec*, int, off64_t);
+ssize_t preadv64(int, const struct iovec*, int, off64_t) __INTRODUCED_IN(24);
+ssize_t pwritev64(int, const struct iovec*, int, off64_t) __INTRODUCED_IN(24);
 #endif
 
 #if defined(__USE_GNU)
-ssize_t process_vm_readv(pid_t, const struct iovec*, unsigned long, const struct iovec*, unsigned long, unsigned long);
-ssize_t process_vm_writev(pid_t, const struct iovec*, unsigned long, const struct iovec*, unsigned long, unsigned long);
+ssize_t process_vm_readv(pid_t, const struct iovec*, unsigned long, const struct iovec*,
+                         unsigned long, unsigned long) __INTRODUCED_IN(23);
+ssize_t process_vm_writev(pid_t, const struct iovec*, unsigned long, const struct iovec*,
+                          unsigned long, unsigned long) __INTRODUCED_IN(23);
 #endif
 
 __END_DECLS
diff --git a/libc/include/sys/vfs.h b/libc/include/sys/vfs.h
index 1fbc8be..9f04b28 100644
--- a/libc/include/sys/vfs.h
+++ b/libc/include/sys/vfs.h
@@ -138,9 +138,9 @@
 #define XFS_SUPER_MAGIC       0x58465342
 
 extern int statfs(const char*, struct statfs*) __nonnull((1, 2));
-extern int statfs64(const char*, struct statfs64*) __nonnull((1, 2));
+extern int statfs64(const char*, struct statfs64*) __nonnull((1, 2)) __INTRODUCED_IN(21);
 extern int fstatfs(int, struct statfs*) __nonnull((2));
-extern int fstatfs64(int, struct statfs64*) __nonnull((2));
+extern int fstatfs64(int, struct statfs64*) __nonnull((2)) __INTRODUCED_IN(21);
 
 __END_DECLS
 
diff --git a/libc/include/sys/wait.h b/libc/include/sys/wait.h
index 2317b02..aba20e5 100644
--- a/libc/include/sys/wait.h
+++ b/libc/include/sys/wait.h
@@ -51,7 +51,7 @@
 
 extern pid_t  wait(int *);
 extern pid_t  waitpid(pid_t, int *, int);
-extern pid_t  wait4(pid_t, int *, int, struct rusage *);
+extern pid_t wait4(pid_t, int*, int, struct rusage*) __INTRODUCED_IN(19);
 
 /* Posix states that idtype_t should be an enumeration type, but
  * the kernel headers define P_ALL, P_PID and P_PGID as constant macros
diff --git a/libc/include/sys/xattr.h b/libc/include/sys/xattr.h
index 39b25b1..070913f 100644
--- a/libc/include/sys/xattr.h
+++ b/libc/include/sys/xattr.h
@@ -35,21 +35,26 @@
 #define XATTR_CREATE 1
 #define XATTR_REPLACE 2
 
-extern int fsetxattr(int fd, const char *name, const void *value, size_t size, int flags);
-extern int setxattr(const char *path, const char *name, const void *value, size_t size, int flags);
-extern int lsetxattr(const char *path, const char *name, const void *value, size_t size, int flags);
+extern int fsetxattr(int fd, const char* name, const void* value, size_t size, int flags)
+  __INTRODUCED_IN(21);
+extern int setxattr(const char* path, const char* name, const void* value, size_t size, int flags)
+  __INTRODUCED_IN(21);
+extern int lsetxattr(const char* path, const char* name, const void* value, size_t size, int flags)
+  __INTRODUCED_IN(21);
 
-extern ssize_t fgetxattr(int fd, const char *name, void *value, size_t size);
-extern ssize_t getxattr(const char *path, const char *name, void *value, size_t size);
-extern ssize_t lgetxattr(const char *path, const char *name, void *value, size_t size);
+extern ssize_t fgetxattr(int fd, const char* name, void* value, size_t size) __INTRODUCED_IN(21);
+extern ssize_t getxattr(const char* path, const char* name, void* value, size_t size)
+  __INTRODUCED_IN(21);
+extern ssize_t lgetxattr(const char* path, const char* name, void* value, size_t size)
+  __INTRODUCED_IN(21);
 
-extern ssize_t listxattr(const char *path, char *list, size_t size);
-extern ssize_t llistxattr(const char *path, char *list, size_t size);
-extern ssize_t flistxattr(int fd, char *list, size_t size);
+extern ssize_t listxattr(const char* path, char* list, size_t size) __INTRODUCED_IN(21);
+extern ssize_t llistxattr(const char* path, char* list, size_t size) __INTRODUCED_IN(21);
+extern ssize_t flistxattr(int fd, char* list, size_t size) __INTRODUCED_IN(21);
 
-extern int removexattr(const char *path, const char *name);
-extern int lremovexattr(const char *path, const char *name);
-extern int fremovexattr(int fd, const char *name);
+extern int removexattr(const char* path, const char* name) __INTRODUCED_IN(21);
+extern int lremovexattr(const char* path, const char* name) __INTRODUCED_IN(21);
+extern int fremovexattr(int fd, const char* name) __INTRODUCED_IN(21);
 
 __END_DECLS