Fixing RSS generation

2 mins
bsd linux gnu osx

Fixing RSS generation

I've made a few changes in the ./create_rss function, so that it works on both Linux and Mac OS X:

  • dont use the -printf option with find
  • dont use --rfc option with date
  • simplified sed commands
  • use simple find command to list files newest to oldest (with sort -r)
  • create RFC 2822 date formats using date +"%a, %d %b %Y %T %z"

Because there is no simple way to generate the dates with a command that works on both Linux and Mac, I use uname to check the OS type (Linux, Darwin, etc), then I set the date using one of two ways.

Here is the relevant code from create_rss:

if [ "$os_type" = "Linux" ];then
  # use GNU date
  pubDate=`date -r "$file" +"%a, %d %b %Y %T %z"`
  force_update=`date -r "$file" "+%s"`
else # Mac, BSD
  # use BSD date
  pubDate=`date -r "$timestamp" +"%a, %d %b %Y %T %z"`
  force_update=`date -r "$timestamp" "+%s"`
fi

Using this, the command ./create_rss posts/ > feed.rss that is used in update_pages should work on Linux, Mac and BSD.

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