Index: absl/base/internal/raw_logging.cc
--- absl/base/internal/raw_logging.cc.orig
+++ absl/base/internal/raw_logging.cc
@@ -36,7 +36,7 @@
 // This preprocessor token is also defined in raw_io.cc.  If you need to copy
 // this, consider moving both to config.h instead.
 #if defined(__linux__) || defined(__APPLE__) || defined(__FreeBSD__) || \
-    defined(__Fuchsia__) || defined(__native_client__) || \
+    defined(__Fuchsia__) || defined(__native_client__) || defined(__OpenBSD__) || \
     defined(__EMSCRIPTEN__) || defined(__ASYLO__)
 
 #include <unistd.h>
@@ -50,7 +50,7 @@
 // ABSL_HAVE_SYSCALL_WRITE is defined when the platform provides the syscall
 //   syscall(SYS_write, /*int*/ fd, /*char* */ buf, /*size_t*/ len);
 // for low level operations that want to avoid libc.
-#if (defined(__linux__) || defined(__FreeBSD__)) && !defined(__ANDROID__)
+#if (defined(__linux__) || defined(__FreeBSD__) || defined(__OpenBSD__)) && !defined(__ANDROID__)
 #include <sys/syscall.h>
 #define ABSL_HAVE_SYSCALL_WRITE 1
 #define ABSL_LOW_LEVEL_WRITE_SUPPORTED 1
