Add getdomainname(2).

libc/Makefile

@@ -494,6 +494,7 @@ unistd/fork.o \
 unistd/fsync.o \
 unistd/ftruncate.o \
 unistd/getcwd.o \
+unistd/getdomainname.o \
 unistd/getegid.o \
 unistd/geteuid.o \
 unistd/getgid.o \

libc/include/unistd.h

@@ -354,6 +354,7 @@ int fsync(int);
 int ftruncate(int, off_t);
 char* getcwd(char*, size_t);
 char* get_current_dir_name(void);
+int getdomainname(char*, size_t);
 gid_t getegid(void);
 uid_t geteuid(void);
 int gethostname(char*, size_t);

libc/unistd/getdomainname.cpp

@@ -0,0 +1,40 @@
+/*******************************************************************************
+
+    Copyright(C) Jonas 'Sortie' Termansen 2014.
+
+    This file is part of the Sortix C Library.
+
+    The Sortix C Library is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or (at your
+    option) any later version.
+
+    The Sortix C Library is distributed in the hope that it will be useful, but
+    WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+    or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
+    License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with the Sortix C Library. If not, see <http://www.gnu.org/licenses/>.
+
+    unistd/getdomainname.cpp
+    Get the domainname.
+
+*******************************************************************************/
+
+#include <errno.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdlib.h>
+
+extern "C" int getdomainname(char* name, size_t len)
+{
+	const char* domainname = getenv("DOMAINNAME");
+	if ( !domainname )
+		domainname = "localdomain";
+	size_t domainname_len = strlen(domainname);
+	if ( len < domainname_len+1 )
+		return errno = ENAMETOOLONG, -1;
+	strcpy(name, domainname);
+	return 0;
+}