Ubuntu 11.10 “cant find” Executable files (NOT .exe's)

Question

i am trying to run an executable file from ubuntu 11.10, and this happens for several different files.

i try to run the file and it says "no such file or directory"

it is not the file because the file was downloaded from a package only, and the exact file runs fines on three of my friends computers. i have recently re installed a new partition of ubuntu 11.10.

it is not a permissions issue because I've tried running it as sudo and ive tried chmod and ive edited the permissions of the actual file to give myself permission and allow it to be run as an executable.

my only guess is that there is some deep setting in Ubuntu somewhere that is accidently activated which prevents me from running executable. i have seen this same question asked in several places and never receive a satisfactory answer. does anyone know why ubuntu is doing this?

please help as soon as possible, i need this program to run today. this is a major ubuntu problem and prevents me from doing anything on this OS.

the code i am running is a simple *.sh function. i navigate to the folder and type ./start.sh

and it executes the file fine. that file calls another executable within a folder in that directory called bin. before doing so, it adds bin to the $PATH so thats not an issue. but when it tries to call that executable, it says it cannot find the file. here is the code of the start.sh

#!/bin/sh

SDKPATH=$(dirname $(readlink -f $0))
UOBPATH=$SDKPATH/share/uobjects/
USPATH=$SDKPATH/share/scripts/

# Edit this script as you want :)
SCRIPT=balltracking.u

$SDKPATH/bin/urbi-launch --start $UOBPATH/* -- --host 0.0.0.0 --port 54000 -f 
$USPATH/$SCRIPT

its not just this file however. ive gon into several other files and tried running executables in a similar manner and the same error comes up. again these same files are executed fine in other computers with the same commands. the only difference is that they have WUBI installed and i am using a partition. i dont know what the issue could be.

Answer 1

Assuming it is both urbi-launch and balltracking.u that are problems, I suggest you try this for each of these two scripts. First go to the directory in which the script resides. Do an ls -Ll <script> and confirm that script grants you execute permissions. The Ll is upper and lower case "el", which give you permissions and traces a symlink in case the script is a link. This guarantees you get the permission on the script and no accidentally the link.

If the permissions look right, then try running each script as a command by invoking it as ./<script>.

If that works, then it is not a problem with Ubuntu, the script executes correctly. If it does not execute correct, please provide the permissions listing and the results of the id command so we can see what you are too.

If the script work from the command line, then it is your start.sh script that has a problem. Have it echo the paths so you can see what is really being used. Another approach to narrow down to the setting of paths is to hard code the explicit path in start.sh for each of the other scripts. If that works, you are guaranteed the problem is in your start.sh scrip and how you determine the path.

Last, I strongly recommend you adopt the following stype for variables in scripts, use ${variable} instead of $variable because adding the curly braces guarantees that other characters are not accidentally added to the variable name creating a new variable with no value.