Very hackish bugfix for:

$ echo foobar | grep foobar /etc/passwd -
grep: lseek: Illegal seek

--- ./src/grep.c.orig	2007-11-09 15:05:44.000000000 +0100
+++ ./src/grep.c	2007-11-09 15:17:23.000000000 +0100
@@ -463,8 +463,9 @@
 	  bufoffset = lseek (fd, 0, SEEK_CUR);
 	  if (bufoffset < 0)
 	    {
-	      error (0, errno, "lseek");
-	      return 0;
+	      goto lseek_failed_hack;
+	      // error (0, errno, "lseek");
+	      // return 0;
 	    }
 	}
 #if defined(HAVE_MMAP)
@@ -474,6 +475,7 @@
     }
   else
     {
+lseek_failed_hack:;
 #if defined(HAVE_MMAP)
       bufmapped = 0;
 #endif