4 files changed, 24 insertions, 5 deletions
diff --git a/src/library.js b/src/library.js
index f6b2a31e..01c0a3f3 100644
--- a/src/library.js
+++ b/src/library.js
@@ -2118,7 +2118,20 @@ LibraryManager.library = {
       return 1;
     }
   },
-  // TODO: Implement initgroups, setgroups (grp.h).
+  // TODO: Implement initgroups (grp.h).
+  setgroups__deps: ['__setErrNo', '$ERRNO_CODES', 'sysconf'],
+  setgroups: function (ngroups, gidset) {
+    // int setgroups(int ngroups, const gid_t *gidset);
+    // https://developer.apple.com/library/mac/#documentation/Darwin/Reference/ManPages/man2/setgroups.2.html
+    if (ngroups < 1 || ngroups > _sysconf({{{ cDefine('_SC_NGROUPS_MAX') }}})) {
+      ___setErrNo(ERRNO_CODES.EINVAL);
+      return -1;
+    } else {
+      // We have just one process/user/group, so it makes no sense to set groups.
+      ___setErrNo(ERRNO_CODES.EPERM);
+      return -1;
+    }
+  },
   gethostid: function() {
     // long gethostid(void);
     // http://pubs.opengroup.org/onlinepubs/000095399/functions/gethostid.html
diff --git a/system/include/libc/sys/unistd.h b/system/include/libc/sys/unistd.h
index b0c6d505..1a414b3c 100644
--- a/system/include/libc/sys/unistd.h
+++ b/system/include/libc/sys/unistd.h
@@ -153,8 +153,8 @@ int     _EXFUN(seteuid, (uid_t __uid ));
 #endif
 int     _EXFUN(setgid, (gid_t __gid ));
 #endif
-#if defined(__CYGWIN__)
-int	_EXFUN(setgroups, (int ngroups, const gid_t *grouplist ));
+#if defined(EMSCRIPTEN) || defined(__CYGWIN__)
+int	_EXFUN(setgroups, (int ngroups, const gid_t *gidset));
 #endif
 int     _EXFUN(setpgid, (pid_t __pid, pid_t __pgid ));
 int     _EXFUN(setpgrp, (void ));
diff --git a/system/include/sys/un.h b/system/include/sys/un.h
index b70425fb..ca002158 100644
--- a/system/include/sys/un.h
+++ b/system/include/sys/un.h
@@ -35,6 +35,7 @@
 
 #include <sys/cdefs.h>
 #include <sys/_types.h>
+#include <sys/socket.h>
 
 /*
  * Definitions for UNIX IPC domain.
diff --git a/tests/unistd/misc.c b/tests/unistd/misc.c
index 4e7ac216..5b0d63d2 100644
--- a/tests/unistd/misc.c
+++ b/tests/unistd/misc.c
@@ -106,7 +106,7 @@ int main() {
   printf("alarm: %d", alarm(42));
   printf(", errno: %d\n", errno);
   errno = 0;
-  printf("ualarm: %d", ualarm(123, 456));
+  printf("ualarm: %ld", ualarm(123, 456));
   printf(", errno: %d\n", errno);
   errno = 0;
 
@@ -117,7 +117,7 @@ int main() {
   printf(", errno: %d\n", errno);
   errno = 0;
 
-  printf("crypt: %d", crypt("foo", "bar"));
+  printf("crypt: %s", crypt("foo", "bar"));
   printf(", errno: %d\n", errno);
   errno = 0;
   char encrypt_block[64] = {0};
@@ -192,5 +192,10 @@ int main() {
   printf(", errno: %d\n", errno);
   errno = 0;
 
+  gid_t groups2[1] = {0};
+  printf("setgroups: %d", setgroups(1, groups2));
+  printf(", errno: %d\n", errno);
+  errno = 0;
+
   return 0;
 }