diff --git a/core/libs/prx/libc/CMakeLists.txt b/core/libs/prx/libc/CMakeLists.txt
index 62f3b7a43b9..953fa7e0c56 100644
--- a/core/libs/prx/libc/CMakeLists.txt
+++ b/core/libs/prx/libc/CMakeLists.txt
@@ -390,8 +390,9 @@ if(BUILD_TESTING)
     target_link_libraries(guest_standard_stream_tests PRIVATE libc)
     configure_windows_unwind(guest_standard_stream_tests)
     add_test(NAME guest_standard_streams COMMAND guest_standard_stream_tests)
+    add_test(NAME guest_standard_streams_closed_stdout COMMAND guest_standard_stream_tests --closed-stdout)
     if(WIN32)
-        set_tests_properties(guest_standard_streams PROPERTIES ENVIRONMENT_MODIFICATION
+        set_tests_properties(guest_standard_streams guest_standard_streams_closed_stdout PROPERTIES ENVIRONMENT_MODIFICATION
             "PATH=path_list_prepend:$<TARGET_FILE_DIR:libc>")
     endif()
     add_test_executable(file_streams_tests ${LIBS_INCLUDE_DIR}/tests/FileStreams.cpp)
diff --git a/core/libs/prx/libc/include/FileStream.hpp b/core/libs/prx/libc/include/FileStream.hpp
index 4ad9fa00b8b..0f51bc7d6d2 100644
--- a/core/libs/prx/libc/include/FileStream.hpp
+++ b/core/libs/prx/libc/include/FileStream.hpp
@@ -71,6 +71,10 @@ class FileStream {
         return _handle;
     }
 
+    bool IsOpen() const {
+        return _handle != nullptr;
+    }
+
     bool IsDynamic() const {
         return _dynamic;
     }
@@ -103,6 +107,7 @@ class FileStream {
         return true;
     }
     void SyncStatus() {
+        if (!_handle) return;
         _guest.readRemaining = 0;
         _guest.writeRemaining = 0;
         _guest.flags = static_cast<std::int16_t>((_guest.flags & ~0x60) |
@@ -110,6 +115,7 @@ class FileStream {
     }
 
     void SyncUnlockedStatus() {
+        if (!_handle) return;
         _guest.readRemaining = 0;
         _guest.writeRemaining = 0;
 #ifdef _WIN32
@@ -129,6 +135,7 @@ class FileStream {
     }
 
     void ClearError() {
+        if (!_handle) return;
         std::clearerr(GetHandle());
         guestError = false;
         SyncStatus();
diff --git a/core/libs/prx/libc/src/FileAndHeap.cpp b/core/libs/prx/libc/src/FileAndHeap.cpp
index 69e7f8d0fe8..16025ecbb94 100644
--- a/core/libs/prx/libc/src/FileAndHeap.cpp
+++ b/core/libs/prx/libc/src/FileAndHeap.cpp
@@ -324,6 +324,11 @@ int APS5_VABI fopen_s_nid_postfix(FileStream** result, const char* filename, con
 }
 
 int APS5_VABI fclose_nid_postfix(FileStream* stream) {
+    if (stream && !stream->IsOpen()) {
+        std::unique_ptr<FileStream> owner(stream->IsDynamic() ? stream : nullptr);
+        errno = 9;
+        return -1;
+    }
     GetNativeStream(stream);
     std::unique_ptr<FileStream> owner(stream->IsDynamic() ? stream : nullptr);
     return stream->Close();
@@ -357,6 +362,7 @@ FileStream* APS5_VABI _ZSt7_FiopenPKcNSt5_IosbIiE9_OpenmodeEi_nid_postfix(const
 }
 
 size_t APS5_VABI fread_nid_postfix(void* buffer, size_t size, size_t count, FileStream* stream) {
+    if (stream && !stream->IsOpen()) { errno = 9; return 0; }
     auto* handle = GetNativeStream(stream);
     if (size == 0 || count == 0) return 0;
     if (!buffer) throw std::runtime_error("fread: null buffer");
@@ -371,6 +377,7 @@ size_t APS5_VABI fread_nid_postfix(void* buffer, size_t size, size_t count, File
 }
 
 size_t APS5_VABI fwrite_nid_postfix(const void* buffer, size_t size, size_t count, FileStream* stream) {
+    if (stream && !stream->IsOpen()) { errno = 9; return 0; }
     auto* handle = GetNativeStream(stream);
     if (size == 0 || count == 0) return 0;
     if (!buffer) throw std::runtime_error("fwrite: null buffer");
@@ -380,6 +387,7 @@ size_t APS5_VABI fwrite_nid_postfix(const void* buffer, size_t size, size_t coun
 }
 
 int APS5_VABI fseeko_nid_postfix(FileStream* stream, std::int64_t offset, int origin) {
+    if (stream && !stream->IsOpen()) { errno = 9; return -1; }
     if (origin != SEEK_SET && origin != SEEK_CUR && origin != SEEK_END) { errno = 22; return -1; }
 #ifdef _WIN32
     auto* native = GetNativeStream(stream);
@@ -396,6 +404,7 @@ int APS5_VABI fseeko_nid_postfix(FileStream* stream, std::int64_t offset, int or
 }
 
 std::int64_t APS5_VABI ftello_nid_postfix(FileStream* stream) {
+    if (stream && !stream->IsOpen()) { errno = 9; return -1; }
 #ifdef _WIN32
     auto* native = GetNativeStream(stream);
     if (IsPipeStream(native)) { errno = 29; return -1; }
@@ -435,12 +444,14 @@ void APS5_VABI rewind_nid_postfix(FileStream* stream) {
 
 int APS5_VABI fputs_nid_postfix(const char* str, FileStream* stream) {
     if (!str) throw std::runtime_error("fputs: null string");
+    if (stream && !stream->IsOpen()) { errno = 9; return -1; }
     const int result = std::fputs(str, GetNativeStream(stream));
     stream->SyncStatus();
     return result;
 }
 
 int APS5_VABI fflush_nid_postfix(FileStream* stream) {
+    if (stream && !stream->IsOpen()) { errno = 9; return -1; }
     std::FILE* native = stream ? GetNativeStream(stream) : nullptr;
 #ifdef __linux__
     if (native && !__fwriting(native)) return 0;
diff --git a/core/libs/prx/libc/src/Formatting.cpp b/core/libs/prx/libc/src/Formatting.cpp
index bc08460a33f..cb1d0d5798b 100644
--- a/core/libs/prx/libc/src/Formatting.cpp
+++ b/core/libs/prx/libc/src/Formatting.cpp
@@ -239,6 +239,7 @@ int APS5_VABI vasprintf_nid_postfix(char** destination, const char* format, VaLi
 }
 
 int APS5_VABI vfprintf_nid_postfix(FileStream* stream, const char* format, VaList* args) {
+    if (stream && !stream->IsOpen()) { errno = 9; return -1; }
     auto* native = GetNativeStream(stream);
 #ifdef _WIN32
     std::string buffer;
@@ -280,6 +281,7 @@ int APS5_VABI fprintf_nid_postfix(FileStream* stream, const char* format, ...) {
 }
 
 int APS5_VABI fscanf_nid_postfix(FileStream* stream, const char* format, ...) {
+    if (stream && !stream->IsOpen()) { errno = 9; return -1; }
     auto* native = GetNativeStream(stream);
 #ifdef _WIN32
     __builtin_sysv_va_list args;
@@ -300,6 +302,7 @@ int APS5_VABI fscanf_nid_postfix(FileStream* stream, const char* format, ...) {
 #ifdef _WIN32
 
 int APS5_VABI printf_nid_postfix(const char* format, ...) {
+    if (!_Stdout_nid_postfix.IsOpen()) { errno = 9; return -1; }
     __builtin_sysv_va_list args;
     __builtin_sysv_va_start(args, format);
     const int result = LibcDetail::PrintWindows(format, args);
@@ -308,6 +311,7 @@ int APS5_VABI printf_nid_postfix(const char* format, ...) {
 }
 
 int APS5_VABI libc_printf_nid_postfix(const char* format, ...) {
+    if (!_Stdout_nid_postfix.IsOpen()) { errno = 9; return -1; }
     __builtin_sysv_va_list args;
     __builtin_sysv_va_start(args, format);
     const int result = LibcDetail::PrintWindows(format, args);
@@ -334,6 +338,7 @@ int APS5_VABI sprintf_nid_postfix(char* buffer, const char* format, ...) {
 #else
 
 int APS5_VABI printf_nid_postfix(const char* format, ...) {
+    if (!_Stdout_nid_postfix.IsOpen()) { errno = 9; return -1; }
     std::va_list args;
     va_start(args, format);
     const int result = HasGuestWideFormat(format) ? LibcDetail::PrintWindows(format, args) : std::vprintf(format, args);
@@ -342,6 +347,7 @@ int APS5_VABI printf_nid_postfix(const char* format, ...) {
 }
 
 int APS5_VABI libc_printf_nid_postfix(const char* format, ...) {
+    if (!_Stdout_nid_postfix.IsOpen()) { errno = 9; return -1; }
     std::va_list args;
     va_start(args, format);
     const int result = HasGuestWideFormat(format) ? LibcDetail::PrintWindows(format, args) : std::vprintf(format, args);
@@ -423,6 +429,7 @@ int APS5_VABI sscanf_s_nid_postfix(const char* buffer, const char* format, ...)
 #endif
 
 int APS5_VABI vprintf_nid_postfix(const char* str, VaList* c) {
+    if (!_Stdout_nid_postfix.IsOpen()) { errno = 9; return -1; }
 #ifdef _WIN32
     return LibcDetail::PrintWindows(str, c);
 #else
@@ -541,6 +548,7 @@ int APS5_VABI printf_s_nid_postfix(const char* format, ...) {
 #endif
 
 int APS5_VABI puts_nid_postfix(const char* s) {
+    if (!_Stdout_nid_postfix.IsOpen()) { errno = 9; return -1; }
     return std::puts(s);
 }
 
diff --git a/core/libs/prx/libc/src/StandardStreams.cpp b/core/libs/prx/libc/src/StandardStreams.cpp
index 69e24de20c2..dc79864a596 100644
--- a/core/libs/prx/libc/src/StandardStreams.cpp
+++ b/core/libs/prx/libc/src/StandardStreams.cpp
@@ -15,6 +15,7 @@ FileStream* __stderrp_nid_postfix = &_Stderr_nid_postfix;
 int __isthreaded_nid_postfix = 1;
 
 int APS5_VABI fgetc_nid_postfix(FileStream* stream) {
+    if (stream && !stream->IsOpen()) { errno = 9; return -1; }
     const int result = std::fgetc(GetNativeStream(stream));
     stream->SyncStatus();
     return result;
@@ -36,6 +37,7 @@ std::int32_t APS5_VABI ungetwc_nid_postfix(std::int32_t value, FileStream* strea
 }
 int APS5_VABI getc_nid_postfix(FileStream* stream) { return fgetc_nid_postfix(stream); }
 int APS5_VABI getc_unlocked_nid_postfix(FileStream* stream) {
+    if (stream && !stream->IsOpen()) { errno = 9; return -1; }
 #ifdef _WIN32
     const int result = _fgetc_nolock(GetNativeStream(stream));
 #else
@@ -47,12 +49,14 @@ int APS5_VABI getc_unlocked_nid_postfix(FileStream* stream) {
 int APS5_VABI __srget_nid_postfix(FileStream* stream) { return fgetc_nid_postfix(stream); }
 int APS5_VABI getchar_nid_postfix() { return fgetc_nid_postfix(__stdinp_nid_postfix); }
 int APS5_VABI fputc_nid_postfix(int value, FileStream* stream) {
+    if (stream && !stream->IsOpen()) { errno = 9; return -1; }
     const int result = std::fputc(value, GetNativeStream(stream));
     stream->SyncStatus();
     return result;
 }
 int APS5_VABI putc_nid_postfix(int value, FileStream* stream) { return fputc_nid_postfix(value, stream); }
 int APS5_VABI putc_unlocked_nid_postfix(int value, FileStream* stream) {
+    if (stream && !stream->IsOpen()) { errno = 9; return -1; }
 #ifdef _WIN32
     const int result = _fputc_nolock(value, GetNativeStream(stream));
 #else
@@ -64,11 +68,13 @@ int APS5_VABI putc_unlocked_nid_postfix(int value, FileStream* stream) {
 int APS5_VABI __swbuf_nid_postfix(int value, FileStream* stream) { return fputc_nid_postfix(value, stream); }
 int APS5_VABI putchar_nid_postfix(int value) { return fputc_nid_postfix(value, __stdoutp_nid_postfix); }
 int APS5_VABI ungetc_nid_postfix(int value, FileStream* stream) {
+    if (stream && !stream->IsOpen()) { errno = 9; return -1; }
     const int result = std::ungetc(value, GetNativeStream(stream));
     stream->SyncStatus();
     return result;
 }
 char* APS5_VABI fgets_nid_postfix(char* buffer, int size, FileStream* stream) {
+    if (stream && !stream->IsOpen()) { errno = 9; return nullptr; }
     if (size <= 0) {
         stream->SetError();
         errno = 22;
@@ -90,6 +96,7 @@ void APS5_VABI clearerr_nid_postfix(FileStream* stream) {
     stream->ClearError();
 }
 int APS5_VABI fileno_nid_postfix(FileStream* stream) {
+    if (stream && !stream->IsOpen()) { errno = 9; return -1; }
 #ifdef _WIN32
     const int descriptor = _fileno(GetNativeStream(stream));
 #else
@@ -99,6 +106,7 @@ int APS5_VABI fileno_nid_postfix(FileStream* stream) {
     return descriptor;
 }
 int APS5_VABI setvbuf_nid_postfix(FileStream* stream, char* buffer, int mode, std::size_t size) {
+    if (stream && !stream->IsOpen()) { errno = 9; return -1; }
     if (mode < 0 || mode > 2) return -1;
     const int native = mode == 0 ? _IOFBF : mode == 1 ? _IOLBF : _IONBF;
     if (native != _IONBF && size == 0) {
diff --git a/core/libs/tests/FileStreams.cpp b/core/libs/tests/FileStreams.cpp
index ff80543263c..bb1361dd5cc 100644
--- a/core/libs/tests/FileStreams.cpp
+++ b/core/libs/tests/FileStreams.cpp
@@ -88,7 +88,7 @@ int main(int argc, char** argv) {
     ExpectException([] { fopen_nid_postfix(nullptr, "r"); });
     FileStream closed(std::tmpfile());
     closed.Close();
-    ExpectException([&] { fflush_nid_postfix(&closed); });
+    Require(fflush_nid_postfix(&closed) == -1 && errno == 9);
     Require(std::remove(argv[1]) == 0);
     errno = 0;
     Require(fopen_nid_postfix(argv[1], "rb") == nullptr);
diff --git a/core/libs/tests/GuestStandardStreams.cpp b/core/libs/tests/GuestStandardStreams.cpp
index 83b97d5ecd7..f1fc3f943ea 100644
--- a/core/libs/tests/GuestStandardStreams.cpp
+++ b/core/libs/tests/GuestStandardStreams.cpp
@@ -5,6 +5,7 @@
 #include <cstring>
 #include <cstdarg>
 #include <cstdint>
+#include <string_view>
 #include <filesystem>
 #include <fstream>
 #include <iterator>
@@ -34,6 +35,10 @@ extern FileStream* __stdoutp_nid_postfix;
 extern FileStream* __stderrp_nid_postfix;
 extern int __isthreaded_nid_postfix;
 int APS5_VABI fprintf_nid_postfix(FileStream*, const char*, ...);
+int APS5_VABI fputs_nid_postfix(const char*, FileStream*);
+int APS5_VABI printf_nid_postfix(const char*, ...);
+int APS5_VABI vprintf_nid_postfix(const char*, void*);
+int APS5_VABI puts_nid_postfix(const char*);
 int APS5_VABI vfprintf_nid_postfix(FileStream*, const char*, void*);
 int APS5_VABI vsprintf_nid_postfix(char*, const char*, void*);
 int APS5_VABI fgetc_nid_postfix(FileStream*);
@@ -80,6 +85,22 @@ static int APS5_VABI WriteFormatted(FileStream* stream, const char* format, ...)
 #endif
     return result;
 }
+static int APS5_VABI PrintStandard(const char* format, ...) {
+#ifdef _WIN32
+    __builtin_sysv_va_list args;
+    __builtin_sysv_va_start(args, format);
+#else
+    std::va_list args;
+    va_start(args, format);
+#endif
+    const int result = vprintf_nid_postfix(format, args);
+#ifdef _WIN32
+    __builtin_sysv_va_end(args);
+#else
+    va_end(args);
+#endif
+    return result;
+}
 static int APS5_VABI FormatString(char* buffer, const char* format, ...) {
 #ifdef _WIN32
     __builtin_sysv_va_list args;
@@ -493,7 +514,38 @@ static void CheckDescriptorAccessModes() {
     Require(std::filesystem::remove(filename));
 }
 
-int main() {
+static void CheckClosedStreamWrites() {
+    FileStream stream(std::tmpfile());
+    Require(freopen_nid_postfix("missing-closed-stream-dir/out.log", "w", &stream) == nullptr);
+    Require(fputs_nid_postfix("text", &stream) == -1 && *__error_nid_postfix() == 9);
+    Require(fprintf_nid_postfix(&stream, "%d", 1) == -1 && *__error_nid_postfix() == 9);
+    Require(fwrite_nid_postfix("text", 1, 4, &stream) == 0 && *__error_nid_postfix() == 9);
+    Require(fputc_nid_postfix('t', &stream) == -1 && *__error_nid_postfix() == 9);
+    Require(putc_unlocked_nid_postfix('t', &stream) == -1 && *__error_nid_postfix() == 9);
+    Require(fflush_nid_postfix(&stream) == -1 && *__error_nid_postfix() == 9);
+    char buffer[8] = {};
+    Require(fread_nid_postfix(buffer, 1, sizeof(buffer), &stream) == 0 && *__error_nid_postfix() == 9);
+    Require(fgetc_nid_postfix(&stream) == -1 && *__error_nid_postfix() == 9);
+    Require(fgets_nid_postfix(buffer, sizeof(buffer), &stream) == nullptr && *__error_nid_postfix() == 9);
+    Require(fseeko_nid_postfix(&stream, 0, SEEK_SET) == -1 && *__error_nid_postfix() == 9);
+    Require(ftello_nid_postfix(&stream) == -1 && *__error_nid_postfix() == 9);
+    Require(fileno_nid_postfix(&stream) == -1 && *__error_nid_postfix() == 9);
+    Require(ferror_nid_postfix(&stream) == 0 && feof_nid_postfix(&stream) == 0);
+    Require(fclose_nid_postfix(&stream) == -1 && *__error_nid_postfix() == 9);
+}
+
+static int CheckClosedStandardOutput() {
+    Require(freopen_nid_postfix("missing-closed-stream-dir/out.log", "w", __stdoutp_nid_postfix) == nullptr);
+    Require(printf_nid_postfix("%d", 1) == -1 && *__error_nid_postfix() == 9);
+    Require(puts_nid_postfix("text") == -1 && *__error_nid_postfix() == 9);
+    Require(PrintStandard("%d", 1) == -1 && *__error_nid_postfix() == 9);
+    Require(fputs_nid_postfix("text", __stdoutp_nid_postfix) == -1 && *__error_nid_postfix() == 9);
+    return 0;
+}
+
+int main(int argc, char** argv) {
+    if (argc > 1 && std::string_view(argv[1]) == "--closed-stdout") return CheckClosedStandardOutput();
+    CheckClosedStreamWrites();
     CheckDescriptorAccessModes();
     Require(_Getmbcurmax_nid_postfix() == 1 && _Getmbcurmax_nid_postfix() == ___mb_cur_max_nid_postfix());
     CheckFlushWhileReading();