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best way to insert a line at the top of a file?

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# 1  
Old 02-09-2009
best way to insert a line at the top of a file?
say I want to insert "this is a test" as the first line into file A, besides

echo "this is a test" > /tmp/tmpfile

cat /tmp/tmpfile fileA >> /tmp/result,

is there any simple way I can do it? thanks
# 2  
Old 02-09-2009
you mean on a file that's already there???

if the file in question isn't so huge it crashes vi, try this:

Code:
vi file << EOF
OWhatever you want as first line
^[:wq!
EOF

Where the ^[ is actually the ESCAPE character entered ( through vi ) with
CONTROL-V and ESC.
# 3  
Old 02-09-2009
but honestly.... no, there isn't a better way.
# 4  
Old 02-09-2009
Also, see this older thread:

https://www.unix.com/unix-advanced-ex...huge-file.html
# 5  
Old 02-09-2009
thanks, just wondering if there is a better way can be used to do this.
# 6  
Old 02-09-2009
Quote:
Originally Posted by fedora
thanks, just wondering if there is a better way can be used to do this.
"Better" is "relative" (and does not have much context)

If you like PERL, then a perl solution is "better".....

What do you mean by "better" ?
# 7  
Old 02-09-2009
you can use the sed "insert" comand:

Code:
the_prompt$ cat thefile

returns:

Code:
line1
line2
line3

Code:
the_prompt$ sed -e '1 i \the line you wanna put first' thefile

returns:

Code:
the line you wanna put first
line1
line2
line3
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