Fix unsigned conversion bug.

Since readi() returns -1 for errors, checking with < against an unsigned value is inadvisable. Checking with != works as intended however.

Fix unsigned conversion bug.
e916d668 · Peter H. Froehlich · Frans Kaashoek · 46293072 · e916d668
--- a/exec.c
+++ b/exec.c
@@ -28,7 +28,7 @@ exec(char *path, char **argv)
  pgdir = 0;
  // Check ELF header
-  if(readi(ip, (char*)&elf, 0, sizeof(elf)) < sizeof(elf))
+  if(readi(ip, (char*)&elf, 0, sizeof(elf)) != sizeof(elf))
    goto bad;
  if(elf.magic != ELF_MAGIC)
    goto bad;