Hour 16

1: Using sed, write a shell function that searches for a word or simple expression in a list of files, printing out a list of matches.

You do not have to support all possible sed expressions. Your function should take the word to look for as its first argument. It should treat its other arguments as a list of files.

HINT: Use double quotes (") instead of single quotes (') to surround your sed script.

A1: One possible implementation is 
sgrep() {
    if [ $# -lt 2 ] ; then
        echo "USAGE: sgrep pattern files" >&2
        exit 1
    fi

    PAT="$1" ; shift ;

    for i in $@ ;
    do
        if [ -f "$i" ] ; then
            sed -n "/$PAT/p" $i
        else
            echo "ERROR: $i not a file." >&2
        fi
    done

    return 0
}
2: Write a sed command that takes as its input the output of the uptime command and prints ...

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