Mention the dangers of the "-pw" option.

[originally from svn r4336]

doc/man-pl.but

@@ -65,7 +65,9 @@ The command-line options supported by \cw{plink} are:
 
 \dt \cw{-pw} \e{password}
 
-\dd Set remote password to \e{password}.
+\dd Set remote password to \e{password}. \e{CAUTION:} this will likely
+make the password visible to other users of the local machine (via
+commands such as \q{\c{w}}).
 
 \dt \cw{\-L} \cw{[}\e{srcaddr}\cw{:]}\e{srcport}\cw{:}\e{desthost}\cw{:}\e{destport}
 

doc/man-pscp.but

@@ -70,7 +70,9 @@ The command-line options supported by \e{pscp} are:
 
 \dt \cw{-pw} \e{password}
 
-\dd Set remote password to \e{password}.
+\dd Set remote password to \e{password}. \e{CAUTION:} this will likely
+make the password visible to other users of the local machine (via
+commands such as \q{\c{w}}).
 
 \dt \cw{-1}
 

doc/man-psft.but

@@ -58,7 +58,9 @@ The command-line options supported by \cw{psftp} are:
 
 \dt \cw{-pw} \e{password}
 
-\dd Set remote password to \e{password}.
+\dd Set remote password to \e{password}. \e{CAUTION:} this will likely
+make the password visible to other users of the local machine (via
+commands such as \q{\c{w}}).
 
 \dt \cw{-1}