Build fails on newest gnu tooltchain

[GoogleCodeExporter]

What steps will reproduce the problem?
make build

What version of the product are you using? On what operating system?
ash 0.5
GCC 4.8.4
Ubuntu 14.04.2 LTS

Please provide any additional information below.
To fix:
Add 
"""
#include <unistd.h>    /* for getpid */
"""

to database.cpp

Original issue reported on code.google.com by simnim...@gmail.com on 18 Aug 2015 at 5:06

[GoogleCodeExporter]

Ah! After looking more carefully at the version, it looks like the version 
included in the install guide that gets curl'd is old. 

So the real issue is actually that the install guide needs an update.

Original comment by simnim...@gmail.com on 18 Aug 2015 at 5:15