the return value $?

Shell Programming and Scripting
1

Could someone tell me that's the return value $? 15 mean? Where can i find out more?

Many thanks

2

What command returned the 15?

3

The return value of 0 (zero) indicates that the process ran ok, anything else is set by the process (script) that you ran.

So the number 15 (probably and exit code) came from the script that you ran. Try searching the script fot the words 'exit 15'

4

hmm, is there no distinguish between 1 and 15? The unix script invokes an other program (natural program). I presume the return value is from the 'natural program'. Is that mean depends on the meaning of return code in 'natural'?