Adding cython v0.20.2 in third-party.

third_party/cython/src/Cython/Includes/posix/unistd.pxd

Index: third_party/cython/src/Cython/Includes/posix/unistd.pxd
diff --git a/third_party/cython/src/Cython/Includes/posix/unistd.pxd b/third_party/cython/src/Cython/Includes/posix/unistd.pxd
new file mode 100644
index 0000000000000000000000000000000000000000..2e115f0099caf4580cfc1bad29cf971768c8ef28
--- /dev/null
+++ b/third_party/cython/src/Cython/Includes/posix/unistd.pxd
@@ -0,0 +1,127 @@
+# http://www.opengroup.org/onlinepubs/009695399/basedefs/unistd.h.html
+
+cdef extern from "unistd.h" nogil:
+
+    #:NULL
+
+    enum: R_OK
+    enum: W_OK
+    enum: X_OK
+    enum: F_OK
+
+    # confstr()
+    #_CS_PATH
+    #_CS_POSIX_*
+
+    enum: SEEK_SET
+    enum: SEEK_CUR
+    enum: SEEK_END
+
+    enum: F_LOCK
+    enum: F_TEST
+    enum: F_TLOCK
+    enum: F_ULOCK
+
+    # pathconf()
+    # _PC_*
+
+    # sysconf()
+    # _SC_*
+
+    enum: STDIN_FILENO	#0
+    enum: STDOUT_FILENO	#1
+    enum: STDERR_FILENO	#2
+
+    #:ctypedef unsigned size_t
+    #:ctypedef signed ssize_t
+    ctypedef int uid_t
+    ctypedef int gid_t
+    ctypedef signed off_t
+    ctypedef signed pid_t
+    ctypedef unsigned useconds_t
+    ctypedef signed intptr_t
+
+    int          access(char *, int)
+    unsigned     alarm(unsigned)
+    int          chdir(char *)
+    int          chown(char *, uid_t, gid_t)
+    int          close(int)
+    size_t       confstr(int, char *, size_t)
+    char        *crypt(char *, char *)
+    char        *ctermid(char *)
+    int          dup(int)
+    int          dup2(int, int)
+    void         encrypt(char[64], int)
+    int          execl(char *, char *, ...)
+    int          execle(char *, char *, ...)
+    int          execlp(char *, char *, ...)
+    int          execv(char *, char *[])
+    int          execve(char *, char *[], char *[])
+    int          execvp(char *, char *[])
+    void        _exit(int)
+    int          fchown(int, uid_t, gid_t)
+    int          fchdir(int)
+    int          fdatasync(int)
+    pid_t        fork()
+    long         fpathconf(int, int)
+    int          fsync(int)
+    int          ftruncate(int, off_t)
+    char        *getcwd(char *, size_t)
+    gid_t        getegid()
+    uid_t        geteuid()
+    gid_t        getgid()
+    int          getgroups(int, gid_t [])
+    long         gethostid()
+    int          gethostname(char *, size_t)
+    char        *getlogin()
+    int          getlogin_r(char *, size_t)
+    int          getopt(int, char * [], char *)
+    pid_t        getpgid(pid_t)
+    pid_t        getpgrp()
+    pid_t        getpid()
+    pid_t        getppid()
+    pid_t        getsid(pid_t)
+    uid_t        getuid()
+    char        *getwd(char *)
+    int          isatty(int)
+    int          lchown(char *, uid_t, gid_t)
+    int          link(char *, char *)
+    int          lockf(int, int, off_t)
+    off_t        lseek(int, off_t, int)
+    int          nice(int)
+    long         pathconf(char *, int)
+    int          pause()
+    int          pipe(int [2])
+    ssize_t      pread(int, void *, size_t, off_t)
+    ssize_t      pwrite(int, void *, size_t, off_t)
+    ssize_t      read(int, void *, size_t)
+    ssize_t      readlink(char *, char *, size_t)
+    int          rmdir(char *)
+    int          setegid(gid_t)
+    int          seteuid(uid_t)
+    int          setgid(gid_t)
+    int          setpgid(pid_t, pid_t)
+    pid_t        setpgrp()
+    int          setregid(gid_t, gid_t)
+    int          setreuid(uid_t, uid_t)
+    pid_t        setsid()
+    int          setuid(uid_t)
+    unsigned     sleep(unsigned)
+    void         swab(void *, void *, ssize_t)
+    int          symlink(char *, char *)
+    void         sync()
+    long         sysconf(int)
+    pid_t        tcgetpgrp(int)
+    int          tcsetpgrp(int, pid_t)
+    int          truncate(char *, off_t)
+    char        *ttyname(int)
+    int          ttyname_r(int, char *, size_t)
+    useconds_t   ualarm(useconds_t, useconds_t)
+    int          unlink(char *)
+    int          usleep(useconds_t)
+    pid_t        vfork()
+    ssize_t      write(int, void *, size_t)
+    char         *optarg
+    int          optind
+    int          opterr
+    int          optopt