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# 1  
Old 12-14-2004
The here document <<


I want to know the use of the here document with the << operator.
Tried to go through some books but the concept was not clear.

Please can any1 expalin me this with a simple example.

# 2  
Old 12-14-2004
ftp machine << EOF
cd dirName
put file1

Above is an example where ftp reads commands till it finds EOF. Inorder for above example to work u have to have .netrc configured ( with out asking for passwd).
# 3  
Old 12-15-2004
2 more examples ..


tr "[a-z]" "[A-Z]" <<EOF
hello world

cat > file1 <<EOF

cat file1
# 4  
Old 12-15-2004
More examples.

Can any1 give me any example for writing interactive programs using the here document.

# 5  
Old 12-15-2004
bhargav has already given you three examples of here document usage.

You say you want to write an "interactive" program using a here document? The very nature and purpose of a here document is to take away user interaction and provide automation.

If you have a specific requirement, then please post what it is you're trying to do.

# 6  
Old 12-15-2004
Thanks i got it

Thanks to all of u,

Now i got the concept of the here document.

The idea is that interactive programs can take input from this here document without waiting for user input.
# 7  
Old 01-23-2006
hi....i understood why the here block is used...but i fail to understand the exact control flow behind it...i mean how does is work and what is the concept behind it? can u kindly throw some light on it? thanks again

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