perl -ne 'print "$1\n" if /aaa=(\d+)\s.*/' xxx.log;
#+END_SRC
+#+BEGIN_SRC fundamental :tangle ./temp/aa.txt
+ aa: 1
+ bb: 2
+ cc: 3
+ dd: 4
+#+END_SRC
+
+#+BEGIN_SRC sh :results output replace
+ perl -wnl -e 'print "==$.: $_"' ./temp/aa.txt
+#+END_SRC
+
+#+RESULTS:
+: ==1:
+: ==2: aa: 1
+: ==3: bb: 2
+: ==4: cc: 3
+: ==5: dd: 4
+
** gnuplog
1. normal