Shell Programming and Scripting

Hi,
Am not very well versed with unix, i wrote a script which will make a new file using cat option like this,


trans.sh

Code:

#!/bin/sh
cat > file1
echo how are you

I wrote only this part since i want to use this concept for something else. What i want to ask is, this script when executed is obviously making file 'file1' which will accept input as what we enter while running script trans.sh with ^D to stop. Ex:- when i run trans.sh it asks for input,lets say i enter "cool" with control+D to stop, so file1 will be made with contents "cool"


Why doesnt file1 has this line 'echo who are you' in it, how can i make script trans.sh recognise the "^D" after line 'echo who are you' inside script
i tried even writing control+D using backticks after this echo line inside script.

Moderator's Comments:

Please use code tags when posting data and code samples!

not sure what 'concept' you're after, but... how about:

Code:

#!/bin/sh 
cat > file1 
echo how are you >> file1

Thanks for the reply...yes we can do what you wrote, but is there not any way by which we can make the script recognize "^D" inside the script...

please let me know where am wrong when i say this..when we write cat > file at command pompt it asks for input to be redirected to file1, 7 input is stopped by "^D"


so when am running trans.sh, as contorl reaches word "cat" it asks for input & this input shoul enter file file1 such as

Admin@comp ~
$ ./trans.sh
juliet
caca


Admin@comp ~
$


Here above while executing script its askign for input which is stopped by ^D & file 1 will contain what we entered while executing trans.sh

Admin@comp ~
$ cat file1
juliet
caca

So, might be if we can make trans.sh recognize "^D" inside the script after line 'echo who are you' , it might consider this line 'echo who are you' as input to be redirected in file1

Sounds like something called a "here doc" might be what you are looking for. If you are looking to have a bunch of lines written from the script into a file, you can use this in either Kshell or bash:

Code:

cat <<endKat >/tmp/test-file
this is line one
this is line two
this is line three
endKat

All lines that follow the cat command, until endKat is reached, are written to the named file (/tmp/test-file in this case). I use endKat as the ending marker string as it isn't likely to be in any text that comes before it.

Have a look at the Kshell documentation for more info on here documents.
http://www2.research.att.com/sw/down.../man1/ksh.html

Thanks bunch for your reply , ya similar to this only i wanted...

So, if we give any string which is not present in the file, it will write everything in named file after cat command until EOF is reached? can you also help me more with exactly what "<<" implies?

Thanks once again for your help !

ps: Also, am able to execute this "test-file" being made here without assigning execute permission on this.