What is on Your Mind?

cat filename|while read line; do ...

sed 's/cat *\([^ ][^ ]*\) *|/<\1/g'

<filename while read line; do ...

while read lone
do
...
done < inputfile

<filename awk '
# mega
# tons
# of
# code
'

awk '
# mega
# tons
# of
# code
' <filename

REDIRECTION
       Before a command is executed, its input and output may be redirected
       using a special notation interpreted by the shell.  Redirection may
       also be used to open and close files for the current shell execution
       environment.  The following redirection operators may precede or appear
       anywhere within a simple command or may follow a command.  Redirections
       are processed in the order they appear, from left to right.

RESERVED WORDS
       Reserved words are words that have a special meaning to the shell.  The
       following words are recognized as reserved when unquoted and either the
       first word of a simple command (see SHELL GRAMMAR below) or the third
       word of a case or for command:

       ! case  do done elif else esac fi for function if in select then until
       while { } time [[ ]]