Ok, back to basics here.
I was completly shocked and dismayed today when one of my apps returned an
error from main. Not so much that it returned an error, that was expected.
But what happened.
I swear that main was supposed to return "int", i.e. some postive/neg
integer of unknown byte lenght(compiler/platform depenendent byte lenght of
course)
So anyways.
I just found out, that on my current system. RedHat ES 3, the return status
from the shell is only an 8 byte unsigned integer. I swear I had more range
before, but that was under different shells and OS's.
So. Is this a OS, shell, or compiler limit?
Meaning, I want to code the correct thing, I just don't know now how to
validly code it, as I had thought main in C/C++ was always supposed to
return (int)
I'm switching my return codes to postive 0-255 value now. Not so bad as the
couple peices of software that interact with this I also now maintain. But
just would like more on this story.
-grant
3  4522 
* Grant Schoep: Ok, back to basics here.
I was completly shocked and dismayed today when one of my apps returned an
error from main. Not so much that it returned an error, that was expected.
But what happened.
I swear that main was supposed to return "int", i.e. some postive/neg
integer of unknown byte lenght(compiler/platform depenendent byte lenght of
course)
So anyways.
I just found out, that on my current system. RedHat ES 3, the return status
from the shell is only an 8 byte unsigned integer.
You mean 8 bits.
I swear I had more range
before, but that was under different shells and OS's.
So. Is this a OS, shell, or compiler limit?
Yes.
Meaning, I want to code the correct thing, I just don't know now how to
validly code it, as I had thought main in C/C++ was always supposed to
return (int)
The language defines only three values: 0, EXIT_SUCCESS, and EXIT_FAILURE,
where 0 and EXIT_SUCCESS have the same conceptual meaning, namely success,
and EXIT_SUCCESS is most probably but not necessarily defined as 0.
--
A: Because it messes up the order in which people normally read text.
Q: Why is it such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?
Grant Schoep wrote: Ok, back to basics here.
I was completly shocked and dismayed today when one of my apps returned an
error from main. Not so much that it returned an error, that was expected.
But what happened.
I swear that main was supposed to return "int", i.e. some postive/neg
integer of unknown byte lenght(compiler/platform depenendent byte lenght
of course)
So anyways.
I just found out, that on my current system. RedHat ES 3, the return
status from the shell is only an 8 byte unsigned integer. I swear I had
more range before, but that was under different shells and OS's.
So. Is this a OS, shell, or compiler limit?
Maybe.
Meaning, I want to code the correct thing, I just don't know now how to
validly code it, as I had thought main in C/C++ was always supposed to
return (int)
In Standard C++, the three values EXIT_FAILURE, EXIST_SUCCESS (from
<cstdlib>) and 0 are the only valid values that main can return. Most
platforms support more values - which is useful to indicate the type of
error - but the details are of course platform specific.
> I'm switching my return codes to postive 0-255 value now. Not so bad as the couple peices of software that interact with this I also now maintain. But
just would like more on this story.
Check this: http://gnu.rtin.bz/prep/standards_13.html This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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