egrep '^To:|^Cc:' /var/spool/mail/$USER | \
cut -c5- | \
awk '{ for (i = 1; i <= NF; i++) print $i }' | \
sed 's/,//g' | grep -v $USER | sort | uniq
awk '/^To:|^Cc:/ { for (i = 2; i <= NF; i++) print $i }' /var/mail/$USER | \
sed 's/,//g' | grep -v [email protected] | sort | uniq
> Software developers creating platform-independent code are advised to avoid using r18 if at all possible. Most compilers provide a mechanism to prevent specific registers from being used for general allocation; portable hand-coded assembler should avoid it entirely. It should not be assumed that treating the register as callee-saved will be sufficient to satisfy the requirements of the platform. Virtualization code must, of course, treat the register as they would any other resource provided to the virtual machine.
From: https://github.com/ARM-software/abi-aa/blob/2bcab1e3b22d5517...