Awesome finds! I've replaced my boards.txt file and the various boards are available (all 4 of them now).
Still, upload errors. The attached screenshot shows that I uploaded ArduinoISP onto the Uno, (added my capacitor), changed to the Board > ATtiny13, uploaded the bootloader, opened the Blink code, changed to Pin4, and tried to upload using 'Upload using Programmer':
avr-g++ -c -g -Os -Wall -fno-exceptions -ffunction-sections -fdata-sections -mmcu=attiny13 -DF_CPU=600000 -MMD -DUSB_VID=null -DUSB_PID=null -DARDUINO=101 -I/home/eljefe/sketchbook/hardware/attiny/cores/core13 /tmp/build1188657047714373045.tmp/Blink.cpp -o /tmp/build1188657047714373045.tmp/Blink.cpp.o
Blink.cpp:10:21: fatal error: Arduino.h: No such file or directory
compilation terminated.
I know I'm close tho! Any more ideas?
Lefty, good news/bad news: those are not upload errors, those are compilation errors (i.e. C++ cannot compile a binary file using a proper core and hence for the proper MCU - Attiny13). Also, if you were able to burn the fuses (which did you choose, BTW?) then for troubleshooting you don't even need to use "Upload using Programmer", just hit the "Verify" button (or Ctrl+R) and when you see no errors, you are good to go. After making sure "Verify" works, you can "Upload".
So, the good news is that the Tiny is hooked up to the Uno properly and the Uno's ArduinoISP sketch is working fine.
The actual error you are getting is caused by the
core13 file's located in a wrong directory.
There are two places for them (in Linux notation):
~/sketchbook/hardware/
tiny/cores/core13 (preferred 'cause it will survive Arduino IDE upgrade)
or
[arduino binary's location]/hardware/
arduino/cores/core13
The bold parts are actually arbitrary (can be anything for as long as the right
boards.txt file is in there), the rest has to be like that. I could not see quite clearly on your printscreen if you're actually using the
/hardware/ after your
~/sketchbook but I can see that you are missing one subdirectory
/cores/ before your
/core13/. Just make sure the core files are under
~/sketchbook/hardware/attiny/cores/core13/ and you should be good to go!