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From: laredotornado on 1 Apr 2008 14:11
Hi,

I'm using Fedora Core 6 Linux with shell zsh. I have two files a.txt
and b.txt, which I want to concatenate to make a third file, "c.txt".
The only difference is in the new file "c.txt", I would like a new
first line. Sadly, this doesn't work

echo 'first_line' | xargs cat a.txt b.txt > c.txt

What can I do? Thanks, - Dave
From: pk on 1 Apr 2008 14:37
laredotornado wrote:

> Hi,
>
> I'm using Fedora Core 6 Linux with shell zsh. I have two files a.txt
> and b.txt, which I want to concatenate to make a third file, "c.txt".
> The only difference is in the new file "c.txt", I would like a new
> first line. Sadly, this doesn't work
>
> echo 'first_line' | xargs cat a.txt b.txt > c.txt

A "new first line" is a line to replace a.txt's first line or a completely
new, extra line?

In the latter case:

echo 'first_line' | cat - a.txt b.txt > c.txt

In the former case:

{ echo 'first_line'; tail -n +2 a.txt; } | cat - b.txt > c.txt

--
All the commands are tested with bash and GNU tools, so they may use
nonstandard features. I try to mention when something is nonstandard (if
I'm aware of that), but I may miss something. Corrections are welcome.
From: Ed Morton on 1 Apr 2008 14:28


On 4/1/2008 1:11 PM, laredotornado wrote:
> Hi,
>
> I'm using Fedora Core 6 Linux with shell zsh. I have two files a.txt
> and b.txt, which I want to concatenate to make a third file, "c.txt".
> The only difference is in the new file "c.txt", I would like a new
> first line. Sadly, this doesn't work
>
> echo 'first_line' | xargs cat a.txt b.txt > c.txt
>
> What can I do? Thanks, - Dave

{ echo 'first_line'; cat a.txt b.txt } > c.txt

From: pk on 1 Apr 2008 14:44
Ed Morton wrote:

> { echo 'first_line'; cat a.txt b.txt } > c.txt

I think you need a ";" after "b.txt" }, or use round parenthesis instead.

--
All the commands are tested with bash and GNU tools, so they may use
nonstandard features. I try to mention when something is nonstandard (if
I'm aware of that), but I may miss something. Corrections are welcome.
From: Ed Morton on 1 Apr 2008 14:32


On 4/1/2008 1:44 PM, pk wrote:
> Ed Morton wrote:
>
>
>>{ echo 'first_line'; cat a.txt b.txt } > c.txt
>
>
> I think you need a ";" after "b.txt" }, or use round parenthesis instead.
>

Yes. Thanks.

Ed.

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