to append few chars at the end of a file

Shell Programming and Scripting
1

hi
i want to open a file at runtime
append few chars at the end of each line
all these i want to have done automatically
how to do it

2 
sed 's/$/a b c/' filename > newfilename
3 
awk '{ print $0 "a b c" }' file

i believe this had been answered many times in the forum