diff --git a/libavformat/matroskadec.c b/libavformat/matroskadec.c
index c12e55ffdf..5430821eb4 100644
--- a/libavformat/matroskadec.c
+++ b/libavformat/matroskadec.c
@@ -547,7 +547,7 @@ ebml_read_master (MatroskaDemuxContext *matroska,
     if (matroska->num_levels >= EBML_MAX_DEPTH) {
         av_log(matroska->ctx, AV_LOG_ERROR,
                "File moves beyond max. allowed depth (%d)\n", EBML_MAX_DEPTH);
-        return AVERROR_NOTSUPP;
+        return AVERROR(ENOSYS);
     }
 
     /* remember level */
diff --git a/libavformat/utils.c b/libavformat/utils.c
index 5bd3b9a9bd..e1729cbc11 100644
--- a/libavformat/utils.c
+++ b/libavformat/utils.c
@@ -2000,14 +2000,14 @@ int av_find_stream_info(AVFormatContext *ic)
 int av_read_play(AVFormatContext *s)
 {
     if (!s->iformat->read_play)
-        return AVERROR_NOTSUPP;
+        return AVERROR(ENOSYS);
     return s->iformat->read_play(s);
 }
 
 int av_read_pause(AVFormatContext *s)
 {
     if (!s->iformat->read_pause)
-        return AVERROR_NOTSUPP;
+        return AVERROR(ENOSYS);
     return s->iformat->read_pause(s);
 }
 
diff --git a/libavformat/vocdec.c b/libavformat/vocdec.c
index d7aa2d3d93..590a9173bc 100644
--- a/libavformat/vocdec.c
+++ b/libavformat/vocdec.c
@@ -47,7 +47,7 @@ static int voc_read_header(AVFormatContext *s, AVFormatParameters *ap)
     header_size = get_le16(pb) - 22;
     if (header_size != 4) {
         av_log(s, AV_LOG_ERROR, "unknown header size: %d\n", header_size);
-        return AVERROR_NOTSUPP;
+        return AVERROR(ENOSYS);
     }
     url_fskip(pb, header_size);
     st = av_new_stream(s, 0);
diff --git a/libavformat/vocenc.c b/libavformat/vocenc.c
index 7ef96bfede..12ca34cac4 100644
--- a/libavformat/vocenc.c
+++ b/libavformat/vocenc.c
@@ -34,7 +34,7 @@ static int voc_write_header(AVFormatContext *s)
 
     if (s->nb_streams != 1
         || s->streams[0]->codec->codec_type != CODEC_TYPE_AUDIO)
-        return AVERROR_NOTSUPP;
+        return AVERROR(ENOSYS);
 
     put_buffer(pb, voc_magic, sizeof(voc_magic) - 1);
     put_le16(pb, header_size);