How to search for text in a file ignoring newlines?

The GNU grep can do it

grep -z 'is\san\sexample\sfile.' file

To fulfill some points which arise in comments there are some modifications to script:

 grep -oz '^[^\n]*\bis\s*an\s*example\s*file\.[^\n]*' file

Regarding huge files I have no imagination of memory limitation but in the case of problem you are free to use sed

sed '/\bis\b/{
          :1
          N
          /file\.\|\(\n.*\)\{3\}/!b1
         }
     /\<is\s*an\s*example\s*file\./p
     D' file

that keep no more than 4-lines (because 4 words in pattern) in memory (\(\n.*\)\{3\}).

Try this:

pcregrep -M '\bThis\s+is\b' <<EOT
This
is
an example
file.
EOT

Related