diff --git a/libmaxsi/include/unistd.h b/libmaxsi/include/unistd.h
index b879023c..e571deeb 100644
--- a/libmaxsi/include/unistd.h
+++ b/libmaxsi/include/unistd.h
@@ -184,6 +184,7 @@ ssize_t write(int, const void*, size_t);
 
 #if defined(_SORTIX_SOURCE)
 int execvpe(const char*, char* const [], char* const []);
+int getdtablesize(void);
 size_t getpagesize(void);
 int memstat(size_t* memused, size_t* memtotal);
 size_t preadall(int fd, void* buf, size_t count, off_t off);
diff --git a/libmaxsi/io.cpp b/libmaxsi/io.cpp
index 5849a64e..9bb02b04 100644
--- a/libmaxsi/io.cpp
+++ b/libmaxsi/io.cpp
@@ -359,6 +359,14 @@ retry:
 		}
 		return templ;
 	}
+
+	// TODO: This has been replaced with sysconf(_SC_OPEN_MAX). This is only
+	// here for compatibility with gzip and should be removed as soon as sysconf
+	// is implemented.
+	extern "C" int getdtablesize(void)
+	{
+		return 0x10000;
+	}
 #endif
 
 }