bash scripting
 

I need to write a bash script to run a program I have written

I have this problem: The script has top check if the executable file (frbv.0.85) is in the current directory:

if [ -f frbv.0.85]; then
frbv.0.85
fi

I want the script checks if frbv.0.85 is in the PATH before exiting with an error

:Pengy: any advice?

thanks

Diego

could you state the problem more clearly? if you want to check for an executable EXEC in directory PATH, why can't you say
if it's not what you are looking for, may be I should read the question again.

could you state the problem more clearly? if you want to check for an executable EXEC in directory PATH, why can't you say
if it's not what you are looking for, may be I should read the question again.

The command "which frbv.0.85" finds the executable "frbv.0.85" by searching your $PATH and echoes the entire path, including the filename itself, to the standard output. E.g. which gcc echoes "/usr/bin/gcc".

Putting a command inside $( ) replaces it with the output of the command inside $( ). And then bash executes the line. E.g. when you have a line "TST=$(which gcc)", bash will execute the command "which gcc". then it replaces "$(which gcc)" with the output of "which gcc". After that it executes the line of script-code, in this case "TST=/usr/bin/gcc".

So the TST variable contains the entire path of the executable where it was first found in $PATH. And now you can test if the file found is executable with "[ -x "$TST]".

I will try to be more clear :D

the name of the exe file is frbv.0.85
to run this program it has to be in the work directory.
In this case I can run it in this way:

$ ./frbv.0.85

if the file is not in the directory there must be a copy of frbv.0.85 in a drectory that is in the path, in this case I can run it in this way:

$ frbv.0.85

I want to check if frbv.0.85 is in the eork directory and in this case I will run it:

if [ -f frbv.0.85]; then
./frbv.0.85
fi

if frbv.0.85 is not in the work directory I want to check if there is a file frbv.0.85 in the path in this case I will run it

if [ ?????? ]; then
frbv.0.85
fi

I do not know how to check if there is a copy of frbv.0.85 in a directory that is in my path

thaks again :D

We posted at exactly the same time.
See my previous post, it solves your problem.

thanks for your advice!

:-D

-=MaGo=-

Off topic guys... but rather than starting a new thread does any body know the relevant commands to insert blank lines when concatenating files - ie if you had

cat a b > c ; d >> c

were a,b,c,d are ordinary text files - the content of the resulting file c is scrunched up - I would like each individual "file" in c to have a blank line between them.

TIA

echo -e "\n\n" >> file

will insert two blank lines

Cheers Strike - that's just what I'm looking for - nice one!

Is there a more efficient way using the shell to separate files using blank lines in the concatenated file? This seems to long winded, even for the shell.

m() { echo -e "\n\n"; } ; cat b > a ; m >> a ; cat c >> a ; m >> a ; cat d >> a ; m >> a ; .................. etc

were b,c,d,........ are files and a is the "concatenated file"

Suppose you had a file e that only had two empty lines.


cat a e b e > c

This might clear things up slightly.

Thanks for the tip Slapnut - just learning at the moment - ( 4 days old - and still very inefficient !! - new to bash scripts/language etc ) so am just trying a few ideas out explicitly at the moment.

In the shell just for learning :

m() { echo -e "\n\n"; } ; cat b > a ; m >> a ; cat c >> a ; m >> a ; cat d >> a ; m >> a ; .................. etc

were b,c,d,........ are files and a is the "concatenated file"


Actually - instead of constantly typing the path to the "concatenated" file "a", I might aswell just assign this to a variable "x" at the start along with the simple function "y"


x=”a” ; y() { echo -e "\n\n"; } ; cat b > $x ; y >> $x ; cat c >> $x ; y >> $x ; cat d >> $x ; y >> $x........etc

were a is the final file and b,c,d.......etc are the files that go to make it up - putting something concrete in:


x="/home/mikki/first" ; y() { echo -e "\n\n"; } ; cat /etc/lilo.conf > $x ; y >> $x ; cat /etc/fstab >> $x ; y >> $x ; fdisk -l /dev/hda >> $x ; y >> $x........etc


I'm hoping to create a simple script soon to accept any number of "appropriate" files for this - it will be general.


Actually - modifying the simple function a little to :

y() { echo -e "\n\n" >> $x; }


we have:


x=”a” ; y() { echo -e "\n\n" >> $x; } ; cat b > $x ; y ; cat c >> $x ; y ; cat d >> $x ; y...........etc

Hi guys :

Can anyone point out the correct way to set up an array in this scenario?

I finished off yesterday with a simple line in the shell which enables me to concatenate any number of files in a neat compilation file at the end -

x=”a” ; y() { echo -e "\n\n" >> $x; } ; cat b > $x ; y ; cat c >> $x ; y ; cat d >> $x ; y...........etc

Today - I've written this simple script to mimic the above - it works great - however I dont know the syntax for using an array variable with read - so I'm limited to the number of variables I set up for read - as an example I ve just used 3.

TIA

Ok - so Ive got the array set up correctly and have redirected the contents of the first element to $compfile.

Now what I want to do is to create a for loop in which every element from the second onwards ie [1]........n gets appended to $compfile, then call y() to put in the blank lines between - The problem is, I dont know the correct syntax and way of setting the for loop up to do this - appreciate any ideas.

TIA