diff --git a/src/ccmain/tessedit.cpp b/src/ccmain/tessedit.cpp
index c9c292b05c..cdbf58ce2e 100644
--- a/src/ccmain/tessedit.cpp
+++ b/src/ccmain/tessedit.cpp
@@ -36,7 +36,6 @@
 #include "stopper.h"
 #include "intmatcher.h"
 #include "chop.h"
-#include "efio.h"
 #include "danerror.h"
 #include "globals.h"
 #ifndef ANDROID_BUILD
diff --git a/src/classify/blobclass.cpp b/src/classify/blobclass.cpp
index ae6e590eb9..457ceb3431 100644
--- a/src/classify/blobclass.cpp
+++ b/src/classify/blobclass.cpp
@@ -24,7 +24,6 @@
 #include <cstdio>
 
 #include "classify.h"
-#include "efio.h"
 #include "featdefs.h"
 #include "mf.h"
 #include "normfeat.h"
@@ -95,12 +94,15 @@ void Classify::LearnBlob(const STRING& fontname, TBLOB* blob,
 // Writes stored training data to a .tr file based on the given filename.
 // Returns false on error.
 bool Classify::WriteTRFile(const STRING& filename) {
+  bool result = false;
   STRING tr_filename = filename + ".tr";
-  FILE* fp = Efopen(tr_filename.string(), "wb");
-  const size_t len = tr_file_data_.length();
-  const bool result =
-      fwrite(&tr_file_data_[0], sizeof(tr_file_data_[0]), len, fp) == len;
-  fclose(fp);
+  FILE* fp = fopen(tr_filename.string(), "wb");
+  if (fp) {
+    const size_t len = tr_file_data_.length();
+    result =
+        fwrite(&tr_file_data_[0], sizeof(tr_file_data_[0]), len, fp) == len;
+    fclose(fp);
+  }
   tr_file_data_.truncate_at(0);
   return result;
 }
diff --git a/src/classify/cutoffs.cpp b/src/classify/cutoffs.cpp
index b10c65f909..dce414ff97 100644
--- a/src/classify/cutoffs.cpp
+++ b/src/classify/cutoffs.cpp
@@ -23,7 +23,6 @@
 #include <cstdio>
 
 #include "classify.h"
-#include "efio.h"
 #include "globals.h"
 #include "helpers.h"
 #include "serialis.h"
diff --git a/src/classify/mastertrainer.cpp b/src/classify/mastertrainer.cpp
index 682d25bb65..90ecd12b97 100644
--- a/src/classify/mastertrainer.cpp
+++ b/src/classify/mastertrainer.cpp
@@ -30,7 +30,6 @@
 #include "allheaders.h"
 #include "boxread.h"
 #include "classify.h"
-#include "efio.h"
 #include "errorcounter.h"
 #include "featdefs.h"
 #include "sampleiterator.h"
@@ -121,7 +120,7 @@ void MasterTrainer::ReadTrainingSamples(const char* page_name,
   const int cn_feature_type = ShortNameToFeatureType(feature_defs, kCNFeatureType);
   const int geo_feature_type = ShortNameToFeatureType(feature_defs, kGeoFeatureType);
 
-  FILE* fp = Efopen(page_name, "rb");
+  FILE* fp = fopen(page_name, "rb");
   if (fp == nullptr) {
     tprintf("Failed to open tr file: %s\n", page_name);
     return;
diff --git a/src/classify/normmatch.cpp b/src/classify/normmatch.cpp
index 44ef7fe268..0522e3d297 100644
--- a/src/classify/normmatch.cpp
+++ b/src/classify/normmatch.cpp
@@ -26,7 +26,6 @@
 #include "classify.h"
 #include "clusttool.h"
 #include "const.h"
-#include "efio.h"
 #include "emalloc.h"
 #include "globals.h"
 #include "helpers.h"
diff --git a/src/classify/outfeat.cpp b/src/classify/outfeat.cpp
index a05319ad3b..261b06fb00 100644
--- a/src/classify/outfeat.cpp
+++ b/src/classify/outfeat.cpp
@@ -21,7 +21,6 @@
 #include "outfeat.h"
 
 #include "classify.h"
-#include "efio.h"
 #include "featdefs.h"
 #include "mfoutline.h"
 #include "ocrfeatures.h"
diff --git a/src/classify/picofeat.cpp b/src/classify/picofeat.cpp
index a0657cb56b..5445fd6ffd 100644
--- a/src/classify/picofeat.cpp
+++ b/src/classify/picofeat.cpp
@@ -21,7 +21,6 @@
 #include "picofeat.h"
 
 #include "classify.h"
-#include "efio.h"
 #include "featdefs.h"
 #include "fpoint.h"
 #include "mfoutline.h"
diff --git a/src/cutil/Makefile.am b/src/cutil/Makefile.am
index 931437021b..596ed9cc70 100644
--- a/src/cutil/Makefile.am
+++ b/src/cutil/Makefile.am
@@ -8,13 +8,13 @@ AM_CPPFLAGS += -DTESS_EXPORTS \
 endif
 
 noinst_HEADERS = \
-    bitvec.h callcpp.h const.h cutil.h cutil_class.h danerror.h efio.h \
+    bitvec.h callcpp.h const.h cutil.h cutil_class.h danerror.h \
     emalloc.h globals.h \
     oldlist.h structures.h
 
 noinst_LTLIBRARIES = libtesseract_cutil.la
 
 libtesseract_cutil_la_SOURCES = \
-    bitvec.cpp callcpp.cpp cutil.cpp cutil_class.cpp danerror.cpp efio.cpp \
+    bitvec.cpp callcpp.cpp cutil.cpp cutil_class.cpp danerror.cpp \
     emalloc.cpp \
     oldlist.cpp structures.cpp
diff --git a/src/cutil/efio.cpp b/src/cutil/efio.cpp
deleted file mode 100644
index 943efc9baf..0000000000
--- a/src/cutil/efio.cpp
+++ /dev/null
@@ -1,55 +0,0 @@
-/******************************************************************************
- ** Filename: efio.c
- ** Purpose:  Utility I/O routines
- ** Author:   Dan Johnson
- ** History:  5/21/89, DSJ, Created.
- **
- ** (c) Copyright Hewlett-Packard Company, 1988.
- ** Licensed under the Apache License, Version 2.0 (the "License");
- ** you may not use this file except in compliance with the License.
- ** You may obtain a copy of the License at
- ** http://www.apache.org/licenses/LICENSE-2.0
- ** Unless required by applicable law or agreed to in writing, software
- ** distributed under the License is distributed on an "AS IS" BASIS,
- ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- ** See the License for the specific language governing permissions and
- ** limitations under the License.
- ******************************************************************************/
-/*----------------------------------------------------------------------------
-          Include Files and Type Defines
-----------------------------------------------------------------------------*/
-#include "efio.h"
-#include "danerror.h"
-#include <cstdio>
-#include <cstring>
-
-#define MAXERRORMESSAGE   256
-
-/*----------------------------------------------------------------------------
-              Public Code
-----------------------------------------------------------------------------*/
-/**
- * This routine attempts to open the specified file in the
- * specified mode.  If the file can be opened, a pointer to
- * the open file is returned.  If the file cannot be opened,
- * an error is trapped.
- * @param Name name of file to be opened
- * @param Mode mode to be used to open file
- * @return Pointer to open file.
- * @note Globals: None
- * @note Exceptions: #FOPENERROR unable to open specified file
- * @note History: 5/21/89, DSJ, Created.
- */
-FILE *Efopen(const char *Name, const char *Mode) {
-  FILE *File;
-  char ErrorMessage[MAXERRORMESSAGE];
-
-  File = fopen (Name, Mode);
-  if (File == nullptr) {
-    sprintf (ErrorMessage, "Unable to open %s", Name);
-    DoError(FOPENERROR, ErrorMessage); 
-    return (nullptr);
-  }
-  else
-    return (File);
-}                                /* Efopen */
diff --git a/src/cutil/efio.h b/src/cutil/efio.h
deleted file mode 100644
index 593e6b66cb..0000000000
--- a/src/cutil/efio.h
+++ /dev/null
@@ -1,32 +0,0 @@
-/******************************************************************************
- **	Filename:	efio.h
- **	Purpose:	Definition of file I/O routines
- **	Author:		Dan Johnson
- **	History:	5/21/89, DSJ, Created.
- **
- **	(c) Copyright Hewlett-Packard Company, 1988.
- ** Licensed under the Apache License, Version 2.0 (the "License");
- ** you may not use this file except in compliance with the License.
- ** You may obtain a copy of the License at
- ** http://www.apache.org/licenses/LICENSE-2.0
- ** Unless required by applicable law or agreed to in writing, software
- ** distributed under the License is distributed on an "AS IS" BASIS,
- ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- ** See the License for the specific language governing permissions and
- ** limitations under the License.
- ******************************************************************************/
-#ifndef   EFIO_H
-#define   EFIO_H
-
-/**----------------------------------------------------------------------------
-          Include Files and Type Defines
-----------------------------------------------------------------------------**/
-#include <cstdio>
-
-#define FOPENERROR      3000
-
-/**----------------------------------------------------------------------------
-          Public Function Prototype
-----------------------------------------------------------------------------**/
-FILE *Efopen(const char *Name, const char *Mode);
-#endif
diff --git a/src/dict/stopper.cpp b/src/dict/stopper.cpp
index 47986aedc7..94e2706eba 100644
--- a/src/dict/stopper.cpp
+++ b/src/dict/stopper.cpp
@@ -27,7 +27,6 @@
 #include "const.h"
 #include "danerror.h"
 #include "dict.h"
-#include "efio.h"
 #include "helpers.h"
 #include "matchdefs.h"
 #include "pageres.h"
diff --git a/src/training/cntraining.cpp b/src/training/cntraining.cpp
index baf6cd5447..1945b5a17c 100644
--- a/src/training/cntraining.cpp
+++ b/src/training/cntraining.cpp
@@ -24,7 +24,6 @@
           Include Files and Type Defines
 ----------------------------------------------------------------------------*/
 #include "oldlist.h"
-#include "efio.h"
 #include "emalloc.h"
 #include "featdefs.h"
 #include "tessopt.h"
@@ -120,7 +119,6 @@ int main(int argc, char *argv[]) {
   Config = CNConfig;
 
   const char  *PageName;
-  FILE  *TrainingPage;
   LIST  CharList = NIL_LIST;
   CLUSTERER *Clusterer = nullptr;
   LIST    ProtoList = NIL_LIST;
@@ -134,11 +132,14 @@ int main(int argc, char *argv[]) {
   int num_fonts = 0;
   while ((PageName = GetNextFilename(argc, argv)) != nullptr) {
     printf("Reading %s ...\n", PageName);
-    TrainingPage = Efopen(PageName, "rb");
-    ReadTrainingSamples(FeatureDefs, PROGRAM_FEATURE_TYPE, 100, nullptr,
-                        TrainingPage, &CharList);
-    fclose(TrainingPage);
-    ++num_fonts;
+    FILE *TrainingPage = fopen(PageName, "rb");
+    ASSERT_HOST(TrainingPage);
+    if (TrainingPage) {
+      ReadTrainingSamples(FeatureDefs, PROGRAM_FEATURE_TYPE, 100, nullptr,
+                          TrainingPage, &CharList);
+      fclose(TrainingPage);
+      ++num_fonts;
+    }
   }
   printf("Clustering ...\n");
   // To allow an individual font to form a separate cluster,
@@ -220,7 +221,8 @@ static void WriteNormProtos(const char *Directory, LIST LabeledProtoList,
   }
   Filename += "normproto";
   printf ("\nWriting %s ...", Filename.string());
-  File = Efopen (Filename.string(), "wb");
+  File = fopen(Filename.string(), "wb");
+  ASSERT_HOST(File);
   fprintf(File, "%0d\n", feature_desc->NumParams);
   WriteParamDesc(File, feature_desc->NumParams, feature_desc->ParamDesc);
   iterate(LabeledProtoList)
diff --git a/src/training/commontraining.cpp b/src/training/commontraining.cpp
index 4e099ca0c0..c244591c20 100644
--- a/src/training/commontraining.cpp
+++ b/src/training/commontraining.cpp
@@ -21,7 +21,6 @@
 #include "classify.h"
 #include "cluster.h"
 #include "clusttool.h"
-#include "efio.h"
 #include "emalloc.h"
 #include "featdefs.h"
 #include "fontinfo.h"
diff --git a/src/training/mergenf.cpp b/src/training/mergenf.cpp
index 94bdc215c9..30d9e641c8 100644
--- a/src/training/mergenf.cpp
+++ b/src/training/mergenf.cpp
@@ -17,7 +17,6 @@
 ******************************************************************************/
 #include "mergenf.h"
 #include "host.h"
-#include "efio.h"
 #include "clusttool.h"
 #include "cluster.h"
 #include "oldlist.h"
diff --git a/src/training/mftraining.cpp b/src/training/mftraining.cpp
index 82863d0bed..98036c73ff 100644
--- a/src/training/mftraining.cpp
+++ b/src/training/mftraining.cpp
@@ -39,7 +39,6 @@
 #include "clusttool.h"
 #include "commontraining.h"
 #include "danerror.h"
-#include "efio.h"
 #include "emalloc.h"
 #include "featdefs.h"
 #include "fontinfo.h"