diff --git a/test/unit/test_c_api.cpp b/test/unit/test_c_api.cpp
index 40da97f9fe..80a8227842 100644
--- a/test/unit/test_c_api.cpp
+++ b/test/unit/test_c_api.cpp
@@ -48,6 +48,7 @@
 #include <sqlite3.h>
 
 #if !defined(_WIN32)
+#include <unistd.h>
 #include <sys/resource.h>
 #endif
 
@@ -6114,8 +6115,10 @@ TEST_F(CApi, open_plenty_of_contexts) {
     struct rlimit open_max_limits;
     getrlimit(RLIMIT_NOFILE, &open_max_limits);
     const rlim_t open_file_max = open_max_limits.rlim_cur;
+    printf("RLIM %ju, sysconf %ju\n", (uintmax_t)open_file_max, (uintmax_t)sysconf(_SC_OPEN_MAX));
     for (rlim_t i = 0; i < open_file_max - 50; i++) {
         FILE *f = fopen("/dev/null", "rb");
+        printf("%ju, ", (uintmax_t)i);
         ASSERT_TRUE(f != nullptr);
         dummyFilePointers.push_back(f);
     }
diff --git a/travis/linux_generic/install.sh b/travis/linux_generic/install.sh
index f2db7e4bbe..6c372b41b6 100755
--- a/travis/linux_generic/install.sh
+++ b/travis/linux_generic/install.sh
@@ -7,3 +7,6 @@ export PROJ_DB_CACHE_DIR="$HOME/.ccache"
 
 # -fno-use-cxa-atexit is needed to build with -coverage
 CC="ccache $CC" CXX="ccache $CXX" CFLAGS="-Werror" CXXFLAGS="-Werror" ./travis/install.sh
+
+printf "ULIMITS:\n"
+ulimit -a