diff --git a/memfile.c b/memfile.c
index a8feea2..a03018f 100644
--- a/memfile.c
+++ b/memfile.c
@@ -65,6 +65,23 @@ size_t cmemfile_read(CMemFile* f, size_t buf_len, char* buf) {
     return le;
 }
 
+int memfile_seek(MemFile* f, int64_t offset, int origin) {
+    if (!f) return 1;
+    int64_t npos = 0;
+    if (origin == SEEK_SET) {
+        npos = offset;
+    } else if (origin == SEEK_CUR) {
+        npos = f->loc + offset;
+    } else if (origin == SEEK_END) {
+        npos = f->len + offset;
+    } else {
+        return 1;
+    }
+    if (npos < 0 || npos > f->len) return 1;
+    f->loc = npos;
+    return 0;
+}
+
 int cmemfile_seek(CMemFile* f, int64_t offset, int origin) {
     if (!f) return 1;
     int64_t npos = 0;
@@ -87,6 +104,11 @@ int64_t cmemfile_tell(CMemFile* f) {
     return f->loc;
 }
 
+int64_t memfile_tell(MemFile* f) {
+    if (!f) return -1;
+    return f->loc;
+}
+
 #define MKTAG(a,b,c,d) ((a) | ((b) << 8) | ((c) << 16) | ((unsigned)(d) << 24))
 #define FFERRTAG(a, b, c, d) (-(int)MKTAG(a, b, c, d))
 #define AVERROR_EOF FFERRTAG( 'E','O','F',' ')
diff --git a/memfile.h b/memfile.h
index 3676998..4c1a792 100644
--- a/memfile.h
+++ b/memfile.h
@@ -34,7 +34,9 @@ void free_memfile(MemFile* f);
 void free_cmemfile(CMemFile* f);
 size_t memfile_read(MemFile* f, char* buf, size_t buf_len);
 size_t cmemfile_read(CMemFile* f, size_t buf_len, char* buf);
+int memfile_seek(MemFile* f, int64_t offset, int origin);
 int cmemfile_seek(CMemFile* f, int64_t offset, int origin);
+int64_t memfile_tell(MemFile* f);
 int64_t cmemfile_tell(CMemFile* f);
 int memfile_readpacket(void* f, uint8_t* buf, int buf_size);
 size_t cmemfile_read2(void* f, size_t buf_len, char* buf);