diff --git a/dcapi/boinc/wu.C b/dcapi/boinc/wu.C
index bf30203477..b6a44f5d18 100644
--- a/dcapi/boinc/wu.C
+++ b/dcapi/boinc/wu.C
@@ -726,7 +726,7 @@ int DC_addWUInput(DC_Workunit *wu, const char *logicalFileName, const char *URL,
 	{
 		va_start(ap, fileMode);
 		char *md5 = va_arg(ap, char *);
-		int size = va_arg(ap, int);
+		size_t size = va_arg(ap, size_t);
 		va_end(ap);
 
 		rfile = _DC_createRemoteFile(logicalFileName, URL, md5, size);
diff --git a/dcapi/common/util.c b/dcapi/common/util.c
index 1a3f96c304..3b5d0c6bbf 100644
--- a/dcapi/common/util.c
+++ b/dcapi/common/util.c
@@ -167,7 +167,7 @@ DC_PhysicalFile *_DC_createPhysicalFile(const char *label,
 }
 
 DC_RemoteFile *_DC_createRemoteFile(const char *label,
-	const char *url, const char *md5, const int size)
+	const char *url, const char *md5, const size_t size)
 {
 	DC_RemoteFile *file;
 
diff --git a/dcapi/doc/tmpl/dc.sgml b/dcapi/doc/tmpl/dc.sgml
index a953539abe..ba34189685 100644
--- a/dcapi/doc/tmpl/dc.sgml
+++ b/dcapi/doc/tmpl/dc.sgml
@@ -270,7 +270,7 @@ units in state %DC_WU_READY (i.e., before the work unit is submitted).
 	%DC_FILE_VOLATILE allows DC-API to optimize the disk space
 	requirements of the application.
 @Varargs: in case using %DC_FILE_REMOTE file mode, the MD5 hash string (char *)
-	and file size information (int) have to be passed.
+	and file size information (size_t) have to be passed.
 @Returns: 0 if successful or a #DC_ErrorCode.
 
 
diff --git a/dcapi/include/dc_common.h b/dcapi/include/dc_common.h
index 3cdaef51c3..4f18e50864 100644
--- a/dcapi/include/dc_common.h
+++ b/dcapi/include/dc_common.h
@@ -21,6 +21,7 @@ extern "C" {
 #include <sys/syslog.h>
 #endif
 
+#include <string.h>
 #include <stdarg.h>
 
 /********************************************************************
@@ -98,7 +99,7 @@ struct _DC_RemoteFile
 	char			*label;
 	char			*url;
 	char			*remotefilehash;
-	int			remotefilesize;
+	size_t			remotefilesize;
 };
 
 
diff --git a/dcapi/include/dc_internal.h b/dcapi/include/dc_internal.h
index f9bbfb8d2b..6316ab30d7 100644
--- a/dcapi/include/dc_internal.h
+++ b/dcapi/include/dc_internal.h
@@ -60,7 +60,7 @@ DC_PhysicalFile *_DC_createPhysicalFile(const char *label, const char *path)
 	__attribute__((visibility("hidden")));
 
 /* Allocates a remote file descriptor */
-DC_RemoteFile *_DC_createRemoteFile(const char *label, const char *url, const char *md5, const int size)
+DC_RemoteFile *_DC_createRemoteFile(const char *label, const char *url, const char *md5, const size_t size)
 	__attribute__((visibility("hidden")));
 
 /* De-allocates a physical file descriptor */