Shell Programming and Scripting

Hi there,

After reading a couple posts on the subject, I came up with the compilation of all advice (that are supposed to work on any situation) and wrote the following script.
But tell me something... Is it that crazy that there's no other way to get the same solution!!!

Code:

#!/bin/bash
exec=$(ps -p $$ --no-heading -o args | cut -d' ' -f2-)
args="$@"; [[ ${#args} -gt 0 ]] && exec=${exec:0:${#exec}-${#args}-1}
exec=$(realpath "$exec")
echo "$exec"

If you have a better or simplier solution, I'd be happy not to be able to tell you that it doesn't work all the time.
Thx in advance
Santiago

Couple of comments:
1. this is a very hard problem. Period. There are many ways to invoke a script
Perderabo has a long discussion about this if you have not already seen the thread.

2. Consider: Do not use exec as a variable name - it is a builtin in bash.

Thx jim mcnamara for your answer,
1) I searched the forum for "perderabo path running script" but could not find the thread you're talking about
2) Thanks for the advice

What's wrong with $0 (or $BASH_SOURCE if the script is being sourced (bash >= 3 only))?

Do you mean just the path, why not simply use:

dirname $0

if you want to assign it to a variable use

path_to_script=$(dirname $0)

or is this not what you mean?

S.

Thank you radoulov.
$0 will only give me the path to the file as the user called it. If my script is in the PATH, the user will call it by it's bare name and I will not be able to know the full path to it. I will study $BASH_SOURCE. What do you mean by (bash >= 3 only)?

Thank you Scrutinizer.
Same explanation as above. If the user calls my script by its bare name, dirname $0 will output nothing.

I suppose I misread the question,
do you need something like this (assuming POSIX shell):

Code:

$ ./s
--> /home/sysadmin/t
$ ./../t/s
--> /home/sysadmin/t
$ cat s
#! /bin/bash

cd -- "${0%/*}" && p="$(pwd -P)"

printf -- '--> %s\n' "$p"