difference...

UNIX for Advanced & Expert Users
1

Hi ALL,

Please tell me the difference between

<< and <

Thanks,

2

In what? Shell?

In a shell, < redirects from a file. Like: cat <filename to have cat read from filename.

In shell, << begins a 'here document', which is like redirecting from a file, but you tell it exactly what the contents are in the script:

# Begins here and continues until it finds EOF on a line by itself
cat <<EOF
this is stuff
this is more stuff
fleeb bargle words
things like $VARIABLE and `echo backticks` will be substituted
The next line does NOT end the here document because it's not at the beginning of the line!
                                        EOF
But the next line will
EOF