diff -r 6456036bbb37 -r edb9f875b7f9 tests/test_printf.c
--- a/tests/test_printf.c	Wed Apr 03 21:22:23 2024 +0200
+++ b/tests/test_printf.c	Fri Apr 12 21:48:12 2024 +0200
@@ -301,9 +301,11 @@
     CxAllocator *alloc = &talloc.base;
     CX_TEST_DO {
         char *oldbuf = buf;
-        size_t len = cx_sprintf_a(alloc, &buf, 16, "Test %d %s", 47, "string");
+        size_t buflen = 16;
+        size_t len = cx_sprintf_a(alloc, &buf, &buflen, "Test %d %s", 47, "string");
         CX_TEST_ASSERT(oldbuf == buf);
         CX_TEST_ASSERT(len == 14);
+        CX_TEST_ASSERT(buflen == 16);
         CX_TEST_ASSERT(0 == memcmp(buf, "Test 47 string", 15));
         CX_TEST_ASSERT(cx_testing_allocator_verify(&talloc));
     }
@@ -317,8 +319,10 @@
     CxAllocator *alloc = &talloc.base;
     char *buf = cxMalloc(alloc, 8);
     CX_TEST_DO {
-        size_t len = cx_sprintf_a(alloc, &buf, 8, "Test %d %s", 47, "foobar");
+        size_t buflen = 8;
+        size_t len = cx_sprintf_a(alloc, &buf, &buflen, "Test %d %s", 47, "foobar");
         CX_TEST_ASSERT(len == 14);
+        CX_TEST_ASSERT(buflen == 15);
         CX_TEST_ASSERT(0 == memcmp(buf, "Test 47 foobar", 15));
         cxFree(alloc, buf);
         CX_TEST_ASSERT(cx_testing_allocator_verify(&talloc));
@@ -333,8 +337,10 @@
     // make it so that only the zero-terminator does not fit
     char *buf = cxMalloc(alloc, 14);
     CX_TEST_DO {
-        size_t len = cx_sprintf_a(alloc, &buf, 14, "Test %d %s", 13, "string");
+        size_t buflen = 14;
+        size_t len = cx_sprintf_a(alloc, &buf, &buflen, "Test %d %s", 13, "string");
         CX_TEST_ASSERT(len == 14);
+        CX_TEST_ASSERT(buflen == 15);
         CX_TEST_ASSERT(0 == memcmp(buf, "Test 13 string", 15));
         cxFree(alloc, buf);
         CX_TEST_ASSERT(cx_testing_allocator_verify(&talloc));
@@ -349,8 +355,10 @@
     CxAllocator *alloc = &talloc.base;
     CX_TEST_DO {
         char *str;
-        size_t len = cx_sprintf_sa(alloc, buf, 16, &str, "Test %d %s", 47, "string");
+        size_t buflen = 16;
+        size_t len = cx_sprintf_sa(alloc, buf, &buflen, &str, "Test %d %s", 47, "string");
         CX_TEST_ASSERT(str == buf);
+        CX_TEST_ASSERT(buflen == 16);
         CX_TEST_ASSERT(len == 14);
         CX_TEST_ASSERT(0 == memcmp(buf, "Test 47 string", 15));
         CX_TEST_ASSERT(0 == memcmp(str, "Test 47 string", 15));
@@ -367,8 +375,10 @@
     CxAllocator *alloc = &talloc.base;
     CX_TEST_DO {
         char *str;
-        size_t len = cx_sprintf_sa(alloc, buf, 16, &str, "Hello %d %s", 4711, "larger string");
+        size_t buflen = 16;
+        size_t len = cx_sprintf_sa(alloc, buf, &buflen, &str, "Hello %d %s", 4711, "larger string");
         CX_TEST_ASSERT(str != buf);
+        CX_TEST_ASSERT(buflen == 25);
         CX_TEST_ASSERT(len == 24);
         CX_TEST_ASSERT(0 == memcmp(str, "Hello 4711 larger string", 25));
         cxFree(alloc, str);
@@ -385,9 +395,11 @@
     CxAllocator *alloc = &talloc.base;
     CX_TEST_DO {
         char *str;
-        size_t len = cx_sprintf_sa(alloc, buf, 16, &str, "Hello %d %s", 112, "string");
+        size_t buflen = 16;
+        size_t len = cx_sprintf_sa(alloc, buf,&buflen, &str, "Hello %d %s", 112, "string");
         CX_TEST_ASSERT(str != buf);
         CX_TEST_ASSERT(len == 16);
+        CX_TEST_ASSERT(buflen == 17);
         CX_TEST_ASSERT(0 == memcmp(str, "Hello 112 string", 17)); // include terminator
         cxFree(alloc, str);
         CX_TEST_ASSERT(cx_testing_allocator_verify(&talloc));