add a test program to read a CDF-5 file with a corrupted header

nc_test/Makefile.am

@@ -105,6 +105,12 @@ test_read.m4 test_write.m4
 # ref_tst_diskless2.cdl is for diff comparison and to produce tst_diskless2.c
 EXTRA_DIST += ref_tst_diskless2.cdl tst_diskless5.cdl CMakeLists.txt
 
+# bad_cdf5_begin.nc is a CDF-5 file with bad variable starting file offsets.
+# It is to be used by tst_open_cdf5.c to see if it can report NC_ENOTNC.
+EXTRA_DIST += bad_cdf5_begin.nc
+TESTS += run_cdf5.sh
+check_PROGRAMS += tst_open_cdf5
+
 # Only clean these on maintainer-clean, because they require m4 to
 # regenerate.
 #MAINTAINERCLEANFILES = test_get.c test_put.c

nc_test/tst_open_cdf5.c

@@ -0,0 +1,25 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <netcdf.h>
+
+#define FILE_NAME "bad_cdf5_begin.nc"
+
+int main(int argc, char *argv[])
+{
+    char *fname=FILE_NAME;
+    int err, nerrs=0, ncid;
+
+    if (argc == 2) fname = argv[1];
+
+    err = nc_open(fname, NC_NOWRITE, &ncid);
+    if (err != NC_ENOTNC) {
+        printf("Error: nc_open() expect NC_ENOTNC but got (%s)\n",
+               nc_strerror(err));
+        nerrs++;
+    }
+    else if (err == NC_NOERR) /* close file */
+        nc_close(ncid);
+
+    return (nerrs > 0);
+}
+