diff --git a/contrib/cvs/src/cvs.h b/contrib/cvs/src/cvs.h
index 20a4c9fd1b43..8079e30b72a3 100644
--- a/contrib/cvs/src/cvs.h
+++ b/contrib/cvs/src/cvs.h
@@ -256,6 +256,8 @@ extern int errno;
 #define	CVSREAD_ENV	"CVSREAD"	/* make files read-only */
 #define	CVSREAD_DFLT	FALSE		/* writable files by default */
 
+#define	CVSREADONLYFS_ENV "CVSREADONLYFS" /* repository is read-only */
+
 #define	RCSBIN_ENV	"RCSBIN"	/* RCS binary directory */
 /* #define	RCSBIN_DFLT		   Set by options.h */
 
@@ -379,6 +381,7 @@ extern char *CVSroot_directory;	/* the directory name */
 
 extern int trace;		/* Show all commands */
 extern int noexec;		/* Don't modify disk anywhere */
+extern int readonlyfs;		/* fail on all write locks; succeed all read locks */
 extern int logoff;		/* Don't write history entry */
 
 #ifdef AUTH_SERVER_SUPPORT
diff --git a/contrib/cvs/src/lock.c b/contrib/cvs/src/lock.c
index f84eccf1852c..1ff6864e4d77 100644
--- a/contrib/cvs/src/lock.c
+++ b/contrib/cvs/src/lock.c
@@ -243,7 +243,7 @@ Reader_Lock (xrepository)
     FILE *fp;
     char *tmp;
 
-    if (noexec)
+    if (noexec || readonlyfs)
 	return (0);
 
     /* we only do one directory at a time for read locks! */
diff --git a/contrib/cvs/src/main.c b/contrib/cvs/src/main.c
index df2d9bfd61de..d0a7059f39e2 100644
--- a/contrib/cvs/src/main.c
+++ b/contrib/cvs/src/main.c
@@ -40,6 +40,7 @@ int really_quiet = FALSE;
 int quiet = FALSE;
 int trace = FALSE;
 int noexec = FALSE;
+int readonlyfs = FALSE;
 int logoff = FALSE;
 mode_t cvsumask = UMASK_DFLT;
 
@@ -399,6 +400,10 @@ main (argc, argv)
     }
     if (getenv (CVSREAD_ENV) != NULL)
 	cvswrite = FALSE;
+    if (getenv (CVSREADONLYFS_ENV) != NULL) {
+	readonlyfs = TRUE;
+	logoff = TRUE;
+    }
 
     /* I'm not sure whether this needs to be 1 instead of 0 anymore.  Using
        1 used to accomplish what passing "+" as the first character to
@@ -729,7 +734,7 @@ main (argc, argv)
 		}
 		(void) strcat (path, "/");
 		(void) strcat (path, CVSROOTADM_HISTORY);
-		if (isfile (path) && !isaccessible (path, R_OK | W_OK))
+		if (readonlyfs == 0 && isfile (path) && !isaccessible (path, R_OK | W_OK))
 		{
 		    save_errno = errno;
 		    error (0, 0, "Sorry, you don't have read/write access to the history file");
diff --git a/contrib/cvs/src/server.c b/contrib/cvs/src/server.c
index 432e9f924d42..bc3f4d2577f4 100644
--- a/contrib/cvs/src/server.c
+++ b/contrib/cvs/src/server.c
@@ -543,7 +543,7 @@ serve_root (arg)
     }
     (void) strcat (path, "/");
     (void) strcat (path, CVSROOTADM_HISTORY);
-    if (isfile (path) && !isaccessible (path, R_OK | W_OK))
+    if (readonlyfs == 0 && isfile (path) && !isaccessible (path, R_OK | W_OK))
     {
 	save_errno = errno;
 	pending_error_text = malloc (80 + strlen (path));