diff --git a/src/coreclr/dlls/mscorpe/pewriter.cpp b/src/coreclr/dlls/mscorpe/pewriter.cpp
index e509412abdabd4..e6833ffd83a603 100644
--- a/src/coreclr/dlls/mscorpe/pewriter.cpp
+++ b/src/coreclr/dlls/mscorpe/pewriter.cpp
@@ -646,7 +646,7 @@ HRESULT CBlobFetcher::Write(FILE* file)
             size_t dwWritten = 0;
             if ((dwWritten = fwrite(m_pIndex[idx].GetRawDataStart(), 1, length, file)) <= 0)
             {
-                return HRESULTFromErrno();
+                return HRESULTFromErr(ferror(file));
             }
             _ASSERTE(dwWritten == length);
         }
@@ -1337,7 +1337,7 @@ HRESULT PEWriter::Open(_In_ LPCWSTR fileName)
     int err = fopen_lp(&m_file, fileName, W("wb"));
 
     if (err != 0)
-        hr = HRESULTFromErrno();
+        hr = HRESULTFromErr(err);
 
     return hr;
 }
@@ -1348,7 +1348,7 @@ HRESULT PEWriter::Seek(int offset)
     if (fseek(m_file, offset, SEEK_SET) == 0)
         return S_OK;
     else
-        return HRESULTFromErrno();
+        return HRESULTFromErr(ferror(m_file));
 }
 
 HRESULT PEWriter::Write(const void *data, int size)
@@ -1375,7 +1375,7 @@ HRESULT PEWriter::Write(const void *data, int size)
             _ASSERTE(dwWritten == (size_t)size);
         }
         else
-            hr = HRESULTFromErrno();
+            hr = HRESULTFromErr(ferror(m_file));
     }
 
     return hr;
@@ -1401,7 +1401,7 @@ HRESULT PEWriter::Close()
     if (err == 0)
         hr = S_OK;
     else
-        hr = HRESULTFromErrno();
+        hr = HRESULTFromErr(err);
 
     m_file = NULL;
 
diff --git a/src/coreclr/ilasm/asmman.cpp b/src/coreclr/ilasm/asmman.cpp
index d63e8c4457d650..fcd3a71c9b4542 100644
--- a/src/coreclr/ilasm/asmman.cpp
+++ b/src/coreclr/ilasm/asmman.cpp
@@ -410,7 +410,7 @@ void    AsmMan::EndAssembly()
                     if (err != 0)
                     {
                         MAKE_UTF8PTR_FROMWIDE(keySourceNameUtf8, ((Assembler*)m_pAssembler)->m_wzKeySourceName);
-                        report->error("Failed to open key file '%s': 0x%08X\n",keySourceNameUtf8,err);
+                        report->error("Failed to open key file '%s': 0x%08X\n",keySourceNameUtf8,HRESULTFromErr(err));
                         m_pCurAsmRef = NULL;
                         return;
                     }
@@ -438,9 +438,9 @@ void    AsmMan::EndAssembly()
                     size_t dwBytesRead;
                     
                     if ((dwBytesRead = fread(m_sStrongName.m_pbPublicKey, 1, m_sStrongName.m_cbPublicKey, fp)) < m_sStrongName.m_cbPublicKey) {
-                        HRESULT hr = HRESULTFromErrno();
+                        HRESULT hr = HRESULTFromErr(ferror(fp));
                         MAKE_UTF8PTR_FROMWIDE(keySourceNameUtf8, ((Assembler*)m_pAssembler)->m_wzKeySourceName);
-                        report->error("Failed to read key file '%s': 0x%d\n",keySourceNameUtf8,hr);
+                        report->error("Failed to read key file '%s': 0x%08X\n",keySourceNameUtf8,hr);
                         m_pCurAsmRef = NULL;
                         fclose(fp);
                         return;
diff --git a/src/coreclr/minipal/Unix/dn-stdio.cpp b/src/coreclr/minipal/Unix/dn-stdio.cpp
index 249b93d427bc6f..c60c72e476eae6 100644
--- a/src/coreclr/minipal/Unix/dn-stdio.cpp
+++ b/src/coreclr/minipal/Unix/dn-stdio.cpp
@@ -83,14 +83,14 @@ int fsetpos_64(FILE* stream, int64_t pos)
 #define ERROR_ALREADY_EXISTS 183L
 #define ERROR_FILENAME_EXCED_RANGE 206L
 
-HRESULT HRESULTFromErrno()
+HRESULT HRESULTFromErr(int err)
 {
     // maps the common I/O errors
     // based on FILEGetLastErrorFromErrno
     
     int32_t win32Err;
 
-    switch(errno)
+    switch(err)
     {
     case 0:
         win32Err = ERROR_SUCCESS;
diff --git a/src/coreclr/minipal/Windows/dn-stdio.cpp b/src/coreclr/minipal/Windows/dn-stdio.cpp
index 9f43dbe4c7bafd..589444e7be10ad 100644
--- a/src/coreclr/minipal/Windows/dn-stdio.cpp
+++ b/src/coreclr/minipal/Windows/dn-stdio.cpp
@@ -30,17 +30,17 @@ int fsetpos_64(FILE* stream, int64_t pos)
     return fsetpos(stream, &fpos);
 }
 
-HRESULT HRESULTFromErrno()
+HRESULT HRESULTFromErr(int err)
 {
     // maps the common I/O errors
     // based on FILEGetLastErrorFromErrno
 
     // stdio functions aren't guaranteed to preserve GetLastError.
-    // errno should be used as source of truth.
+    // errno/ferror should be used as source of truth.
     
     DWORD win32Err;
 
-    switch(errno)
+    switch(err)
     {
     case 0:
         win32Err = ERROR_SUCCESS;
diff --git a/src/coreclr/minipal/dn-stdio.h b/src/coreclr/minipal/dn-stdio.h
index 41464d2069c8e4..bb70dc2d1d3148 100644
--- a/src/coreclr/minipal/dn-stdio.h
+++ b/src/coreclr/minipal/dn-stdio.h
@@ -12,4 +12,4 @@ int u16_fopen_s(FILE** stream, const WCHAR* path, const WCHAR* mode);
 int64_t fgetsize(FILE* stream);
 int64_t ftell_64(FILE* stream);
 int fsetpos_64(FILE* stream, int64_t pos);
-HRESULT HRESULTFromErrno();
+HRESULT HRESULTFromErr(int err);