Index: R/digest.R
===================================================================
--- R/digest.R	(revision 45)
+++ R/digest.R	(working copy)
@@ -54,6 +54,9 @@
      if (!isTRUE(!file.info(object)$isdir)) {
        stop("The specified pathname is not a file: ", object)
      }
+     if (file.access(object, 4)) {
+       stop("The specified file is not readable: ", object)
+     }
    }
    ## if skip is auto (or any other text for that matter), we just turn it
    ## into 0 because auto should have been converted into a number earlier
@@ -68,6 +71,3 @@
                 PACKAGE="digest")
    return(val)
 }
-
-
-
Index: tests/digestTest.R
===================================================================
--- tests/digestTest.R	(revision 45)
+++ tests/digestTest.R	(working copy)
@@ -105,3 +105,10 @@
 h1 = as.character(md5sum(fname))
 h2 = digest(fname, algo="md5", file=TRUE)
 stopifnot( identical(h1,h2) )
+
+# Make sure we don't core dump with unreadable files.
+fname <- tempfile()
+cat("Hello World, you won't have access to read me", file=fname)
+on.exit(unlink(fname))
+Sys.chmod(fname, mode="0000")
+try(digest(fname, file=TRUE))
Index: DESCRIPTION
===================================================================
--- DESCRIPTION	(revision 45)
+++ DESCRIPTION	(working copy)
@@ -1,5 +1,5 @@
 Package: digest
-Version: 0.5.1
+Version: 0.5.2
 Date: $Date$
 Author: Dirk Eddelbuettel <edd@debian.org> with contributions 
  by Antoine Lucas, Jarek Tuszynski, Henrik Bengtsson, Simon Urbanek,
Index: src/digest.c
===================================================================
--- src/digest.c	(revision 45)
+++ src/digest.c	(working copy)
@@ -135,7 +135,7 @@
       unsigned char md5sum[16];
 
       if (!(fp = fopen(txt,"rb"))) {
-        error(strcat("Cannot open input file: ", txt));    
+        error("Cannot open input file: %s", txt);
         return(NULL);
       }
       if (skip > 0) fseek(fp, skip, SEEK_SET);
@@ -167,7 +167,7 @@
       unsigned char sha1sum[20];
       
       if (!(fp = fopen(txt,"rb"))) {
-        error(strcat("Cannot open input file: ", txt));    
+        error("Cannot open input file: %s", txt);
         return(NULL);
       }
       if (skip > 0) fseek(fp, skip, SEEK_SET);
@@ -196,7 +196,7 @@
       unsigned long val;
       
       if (!(fp = fopen(txt,"rb"))) {
-        error(strcat("Cannot open input file: ", txt));    
+        error("Cannot open input file: %s", txt);
         return(NULL);
       }
       if (skip > 0) fseek(fp, skip, SEEK_SET);
@@ -224,7 +224,7 @@
       unsigned char sha256sum[32];
       
       if (!(fp = fopen(txt,"rb"))) {
-        error(strcat("Cannot open input file: ", txt));    
+        error("Cannot open input file: %s", txt);
         return(NULL);
       }
       if (skip > 0) fseek(fp, skip, SEEK_SET);