I found it, I'm posting the solution in case someone else needs to know how to do it:
[myTextView selectAll:self];
Pregunta
I know this must be very simple... but I'm searching for about 30 mins and didn't find anything... How do you select programmatically all the text in a NSTextView? Thanks for your help Massy
Solución
I found it, I'm posting the solution in case someone else needs to know how to do it:
[myTextView selectAll:self];