I’m an “old school” Unix user, who grew up on sed, awk & Sendmail, but many people still use sed & its syntax from the Unix or Linux command-line daily, so this is a quick note on how to use ‘sed’ when you’re working with URLs.<\/p>\n
The ‘trick’ here (if there is one) is that most sed examples are for using it to substitute characters in a text line or file.
\neg: changing http:\/\/this-site\/ to http:\/\/that-site\/
\nBut the usual delimiter of the text to be changed is the ‘\/’ (slash or divide-sign) character, which simply doesn’t work when the text your substituting also contains the ‘\/’ (ie: URLs).<\/p>\n
Please you don’t have to use the ‘\/’ to delimit search & replace text in sed command lines, you can use (just about\/within reason) any single character you like (eg: the ‘%’ (percent-sign) character), just as long as you use it consistently in your sed command line.<\/p>\n
So if you’re using sed to substitute text in a URL, use the % to delimit the text to search for and the text to replace it with.
\nHere’s some examples:<\/p>\n
Eg 1: We want to change all references of http:\/\/google.com to https:\/\/google.com in an inputfile, so a sed command line for this may be:<\/p>\n
Don’t forget that “man sed” is your friend & there’s an O’Reilly “sed” book too on it for much “sed goodness”.<\/p>\n","protected":false},"excerpt":{"rendered":" I’m an “old school” Unix user, who grew up on sed, awk & Sendmail, but many people still use sed & its syntax from the Unix or Linux command-line daily, so this is a quick note on how to use … Continue reading sed 's%http:\/\/google.com%https:\/\/google.com%g' inputfile > outputfile
\n<\/code>
\nEg 2: You have a shell variable containing a URL, say $thisurl which you want to change to the contents of another variable $thaturl :<\/p>\nsed \"s%$thisurl%$thaturl%g\"
\n<\/code>
\nNote: the use of the double-quotes (“) character to allow shell variable expansion within the sed command.<\/p>\n