`./gen.pl` is horribly slow

[cvengler]

I did this

engler@lennon:~/src/curl/docs/cmdline-opts$ time ./gen.pl mainpage *.d > /dev/null 
    1m49.23s real     0m54.19s user     0m53.80s system

I expected the following

A faster generation of the man-page.

curl/libcurl version

git master

operating system

OpenBSD lennon 7.1 GENERIC.MP#3 amd64

[cvengler]

My first impression is that fde0925 introduced the decrease in the performance. Before that commit, the results were as follows:

engler@lennon:~/src/curl/docs/cmdline-opts$ time ./gen.pl mainpage *.d > /dev/null 
    0m28.47s real     0m23.97s user     0m03.54s system