arg 2 to err() and friends, and warnings are promoted to errors.
This allows the following revisions to be reverted:
rev 1.39 src/bin/cp/cp.c
rev 1.26 src/bin/chmod/chmod.c
rev 1.40 src/bin/rm/rm.c
The following revisions can already be reverted, because they were
already covered by WFORMAT=0:
rev 1.8 src/bin/ls/lomac.c
rev 1.63 src/bin/ls/ls.c
rev 1.8 src/bin/ps/lomac.c
rev 1.34 src/bin/rcp/rcp.c
a3ee32f3f7