For now it just smartly copies it from the APK zip to the filesystem and chmods it.
For testing:
(in an adb shell)
CAMLI_AUTH=userpass:USER:PASS /data/data/org.camlistore/files/camput.bin --server=https://server.example.com file -vivify /sdcard/DCIM/Camera/IMG_20130126_143719.jpg
... which now works, as of commit 51e88c7434 (camput: run in an Android linux non-cgo environment)
Change-Id: I32a7e1e28fdf781bec5156271a4b33f5bd3b8b83
Brad Fitzpatrick