Hi, Am Mittwoch, den 28.07.2021, 10:56 +0200 schrieb Ahmad Fatoum: > Hello Andrej, > > On 23.07.21 12:18, Andrej Picej wrote: > > Hi all, > > > > I have a question about Hush shell and the use of its conditional statements. > > We have come upon an interesting behaviour with its return values. > > > > If the condition of the if statement is not true then the return value is 1 (error code), and if the condition is true the return value is 0 (success). > > > > Simple test: > > > #!/bin/sh > > > if [ 0 -gt 1 ]; then > > > echo "0 gt 1, Ret: $?" > > > fi > > > echo "Ret: $?" > > > > > > if [ 2 -gt 1 ]; then > > > echo "2 gt 1, Ret: $?" > > > fi > > > echo "Ret: $?" > > > > Output: > > > Ret: 1 > > > 2 gt 1, Ret: 0 > > > Ret: 0 > > > > This means that if, for example the first if statement (where condition is not met) would be at the end of a script the return value of that whole script would be 1 (error code). > > I don't think this follows standard shell behaviour. If if statement condition is not met this doesn't mean that the return value should be an error code, right? > > Using other shells (bash for example) we can see that the returned value in both cases is 0, which is expected (IMO). > > > > This behaviour is not new to the Hush or barebox as I could reproduce it on various previous barebox versions (2013.08.0, 2017.12.0 and 2019.11.0). > > > > Of course, this problem can be easily avoided if at the end of every script we use explicit exit 0. This is doable, but a little annoying. > > > > Although this is not a deal-breaker for us, I was wondering what is the reason behind this? How do you get around this and are there any plans to fix/modify this in the future so it follows the > > behaviour of other shells? > > I talked with Sascha once before (off-list) about a similar issue. Missing error handling > results in > > [ x1 -eq x2 ] && echo yes || echo no > > printing yes. > > We agreed that it's ok to break scripts relying on clear hush bugs like this. > > I'd thus recommend you to send a patch to fix hush instead of working around it. shellcheck says: SC2015: Note that A && B || C is not if-then-else. C may run when A is true. So I would think that B is maybe allowed to run before A, too. But, I do not know if Hush specifies execution order here. Regards, Denis > > Cheers, > Ahmad > > > > > Thank you for your answer. > > > > Best regards, > > Andrej > > > > _______________________________________________ > > barebox mailing list > > barebox@xxxxxxxxxxxxxxxxxxx > > http://lists.infradead.org/mailman/listinfo/barebox > > > > Diehl Connectivity Solutions GmbH Geschäftsführung: Horst Leonberger Sitz der Gesellschaft: Nürnberg - Registergericht: Amtsgericht Nürnberg: HRB 32315 ________________________________ Der Inhalt der vorstehenden E-Mail ist nicht rechtlich bindend. Diese E-Mail enthaelt vertrauliche und/oder rechtlich geschuetzte Informationen. Informieren Sie uns bitte, wenn Sie diese E-Mail faelschlicherweise erhalten haben. Bitte loeschen Sie in diesem Fall die Nachricht. Jede unerlaubte Form der Reproduktion, Bekanntgabe, Aenderung, Verteilung und/oder Publikation dieser E-Mail ist strengstens untersagt. - Informationen zum Datenschutz, insbesondere zu Ihren Rechten, erhalten Sie unter: https://www.diehl.com/group/de/transparenz-und-informationspflichten/ The contents of the above mentioned e-mail is not legally binding. This e-mail contains confidential and/or legally protected information. Please inform us if you have received this e-mail by mistake and delete it in such a case. Each unauthorized reproduction, disclosure, alteration, distribution and/or publication of this e-mail is strictly prohibited. - For general information on data protection and your respective rights please visit: https://www.diehl.com/group/en/transparency-and-information-obligations/ _______________________________________________ barebox mailing list barebox@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/barebox
