Fix that skipping fails if target is 2nd frame

With bSeekForwardOnly the current file position should be an inclusive boundary,
but because the binary search stops if the search region (high-low) becomes
header_size, the current frame wasn't found. Because trjconv always reads the
first frame before calling seek, it failed if the target was the 2nd frame.

Fixes #1154

Change-Id: Id4151f0106abdb68d6067f02fe2927a4ec6d77a0

diff --git a/src/gmxlib/libxdrf.c b/src/gmxlib/libxdrf.c
index d3209280241d9c746c01700b42f4c1aca5de0869..dd56225b548d38e697a25c9ee0f5b68bd029730f 100644 (file)
--- a/src/gmxlib/libxdrf.c
+++ b/src/gmxlib/libxdrf.c
@@ -1466,7 +1466,7 @@ int xdr_xtc_seek_time(real time, FILE *fp, XDR *xdrs, int natoms, gmx_bool bSeek
 
     if (bSeekForwardOnly)
     {
-        low = gmx_ftell(fp);
+        low = gmx_ftell(fp)-header_size;
     }
     if (gmx_fseek(fp, 0, SEEK_END))
     {