That's the tip of the iceberg. You can do anything in awk.

for a in *.c do awk 'function lensort(a,zerp, x,tmp) {for (x = 1 ; x < zerp ; x++) {tmp = a[x]; if (length(a[x + 1]) < length(a[x])) {a[x] = a[x + 1]; a[x + 1] = tmp}}} /^(int|void|char|struct|long|float)/ {while (x < 2) {getline ; arr[$1] = (substr($0,1,1) == "{") ? "\n" : $0 "\n" ; x++}} END {lensort(arr,v); for (c in arr) {printf "%s\n",(length(arr[c]) > 0) ? arr[c] : ""}}' ${a} done