# Stop with non-zero exit status **URL:** \ **Category:** Uncategorized\ **Created:** [October 13, 2021, 9:47am UTC](https://fortran-lang.discourse.group/t/stop-with-non-zero-exit-status/2062 "2021-10-13T09:47:29Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![lmiq](https://yyz2.discourse-cdn.com/free1/user_avatar/fortran-lang.discourse.group/lmiq/32/555_2.png) [@lmiq](https://fortran-lang.discourse.group/u/lmiq)\ **Post date:** [October 13, 2021, 9:47am UTC](https://fortran-lang.discourse.group/t/stop-with-non-zero-exit-status/2062/1 "2021-10-13T09:47:29Z")
Searching for this question I found this SO thread, and the suggestion is to use `stop N`. Is that a standard way to do it? Seems from the discussion that sometimes the number gets printed, or not, depending on the OS or the compiler. What I want is a flag to allow easier handling of errors from the output of a Fortran program, using an upper level script. > ---
**Author:** ![vmagnin](https://yyz2.discourse-cdn.com/free1/user_avatar/fortran-lang.discourse.group/vmagnin/32/28_2.png) [@vmagnin](https://fortran-lang.discourse.group/u/vmagnin)\ **Post date:** [October 13, 2021, 9:58am UTC](https://fortran-lang.discourse.group/t/stop-with-non-zero-exit-status/2062/2 "2021-10-13T09:58:58Z")
The Fortran 2018 standard says: > If the stop-code is an integer, it is recommended that the value be used as the process exit status, if the processor supports that concept. > If QUIET= is omitted or the scalar-logical-expr has the value false: > • … > • if a stop code is specified, it is **recommended** that it be made available by formatted output to the same unit. (ERROR\_UNIT, I think) Note there is also the `ERROR STOP` statement: > Execution of a STOP statement initiates normal termination of execution. Execution of an ERROR STOP statement initiates error termination of execution. ---
**Author:** ![vmagnin](https://yyz2.discourse-cdn.com/free1/user_avatar/fortran-lang.discourse.group/vmagnin/32/28_2.png) [@vmagnin](https://fortran-lang.discourse.group/u/vmagnin)\ **Post date:** [October 13, 2021, 11:41am UTC](https://fortran-lang.discourse.group/t/stop-with-non-zero-exit-status/2062/3 "2021-10-13T11:41:45Z")
> **[How does Fortran stderr stop return code work?](https://www.scivision.dev/fortran-stderr-stop-return-code/)** > > From 1956 Fortran I through Fortran 2018 standard, an integer stop value is generally returned. In Fortran 2018, variable error stop is finally allowed. ---
**Author:** ![everythingfunctional](https://yyz2.discourse-cdn.com/free1/user_avatar/fortran-lang.discourse.group/everythingfunctional/32/176_2.png) [@everythingfunctional](https://fortran-lang.discourse.group/u/everythingfunctional)\ **Post date:** [October 13, 2021, 12:07pm UTC](https://fortran-lang.discourse.group/t/stop-with-non-zero-exit-status/2062/4 "2021-10-13T12:07:29Z")
A process exit code has not always been a thing, and thus the Fortran standard cannot mandate anything about it. I will note that I have had fairly good luck with `stop n` passing `n` as the exit code on all platforms and compilers that I care about. I will note that detecting it on Windows is occasionally a bit finicky, I suspect more due to the idiosyncrasies of the `cmd` and/or `batch` shells than problems in the Fortran compilers or run-time systems. ---
**Author:** ![lmiq](https://yyz2.discourse-cdn.com/free1/user_avatar/fortran-lang.discourse.group/lmiq/32/555_2.png) [@lmiq](https://fortran-lang.discourse.group/u/lmiq)\ **Post date:** [October 13, 2021, 12:34pm UTC](https://fortran-lang.discourse.group/t/stop-with-non-zero-exit-status/2062/5 "2021-10-13T12:34:34Z")
When using `stop 1` (for example), this becomes output on the program termination, like: ```auto ERROR: Invalid input parameter. STOP 1 ``` Is it possible to suppress that printing? ---
**Author:** ![themos](https://yyz2.discourse-cdn.com/free1/user_avatar/fortran-lang.discourse.group/themos/32/521_2.png) [@themos](https://fortran-lang.discourse.group/u/themos)\ **Post date:** [October 13, 2021, 1:08pm UTC](https://fortran-lang.discourse.group/t/stop-with-non-zero-exit-status/2062/6 "2021-10-13T13:08:06Z")
> STOP 1, QUIET=.TRUE. is the Standard’s way ---
**Author:** ![lmiq](https://yyz2.discourse-cdn.com/free1/user_avatar/fortran-lang.discourse.group/lmiq/32/555_2.png) [@lmiq](https://fortran-lang.discourse.group/u/lmiq)\ **Post date:** [October 13, 2021, 1:45pm UTC](https://fortran-lang.discourse.group/t/stop-with-non-zero-exit-status/2062/7 "2021-10-13T13:45:42Z")
That is perfect, thank you! ---
**Author:** ![vmagnin](https://yyz2.discourse-cdn.com/free1/user_avatar/fortran-lang.discourse.group/vmagnin/32/28_2.png) [@vmagnin](https://fortran-lang.discourse.group/u/vmagnin)\ **Post date:** [October 13, 2021, 2:43pm UTC](https://fortran-lang.discourse.group/t/stop-with-non-zero-exit-status/2062/8 "2021-10-13T14:43:07Z")
By the way, that blog has many interesting short and recent articles in the Fortran category: > **[fortran](https://www.scivision.dev/categories/fortran/)** > > fortran categories taxonomy ---
**Author:** ![certik](https://yyz2.discourse-cdn.com/free1/user_avatar/fortran-lang.discourse.group/certik/32/4_2.png) [@certik](https://fortran-lang.discourse.group/u/certik)\ **Post date:** [October 13, 2021, 3:40pm UTC](https://fortran-lang.discourse.group/t/stop-with-non-zero-exit-status/2062/9 "2021-10-13T15:40:12Z")
I have also been using `stop 1`, that seemed to work everywhere. Recently I switched to `error stop`. Regarding the `quiet` part, with GFortran 11.0.1 I get: ```auto $ gfortran a.f90 a.f90:1:7: 1 | STOP 1, QUIET=.TRUE. | 1 Error: Syntax error in STOP statement at (1) ``` So I don’t know if I am doing anything wrong. ---
**Author:** ![lmiq](https://yyz2.discourse-cdn.com/free1/user_avatar/fortran-lang.discourse.group/lmiq/32/555_2.png) [@lmiq](https://fortran-lang.discourse.group/u/lmiq)\ **Post date:** [October 13, 2021, 4:48pm UTC](https://fortran-lang.discourse.group/t/stop-with-non-zero-exit-status/2062/10 "2021-10-13T16:48:22Z")
It seems that it is feature not implemented yet? [https://gcc.gnu.org/bugzilla/show\_bug.cgi?id=84519](https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84519) ---
**Author:** ![certik](https://yyz2.discourse-cdn.com/free1/user_avatar/fortran-lang.discourse.group/certik/32/4_2.png) [@certik](https://fortran-lang.discourse.group/u/certik)\ **Post date:** [October 13, 2021, 4:56pm UTC](https://fortran-lang.discourse.group/t/stop-with-non-zero-exit-status/2062/11 "2021-10-13T16:56:51Z")
> [@certik](#): > > `STOP 1, QUIET=.TRUE.` Looks like GFortran’s parser cannot parse it yet. In LFortran we can parse it: ```console $ cat b.f90 program test STOP 1, QUIET=.TRUE. end $ lfortran --show-ast b.f90 (TranslationUnit [(Program test () [] [] [] [(Stop 0 1 (Logical .true.) ())] [])]) ``` But the `quiet=.true.` gets lost by the time it gets to ASR: ```console $ lfortran --show-asr b.f90 (TranslationUnit (SymbolTable 1 {test: (Program (SymbolTable 2 {}) test [] [(Stop (ConstantInteger 1 (Integer 4 [])))])}) []) ``` And by the time it gets to LLVM, also the non-zero exit code gets lost: ```auto $ lfortran --show-llvm b.f90 ; ModuleID = 'LFortran' source_filename = "LFortran" @0 = private unnamed_addr constant [6 x i8] c"STOP\0A\00", align 1 define i32 @main() { .entry: call void (i8*, ...) @_lfortran_printf(i8* getelementptr inbounds ([6 x i8], [6 x i8]* @0, i32 0, i32 0)) call void @exit(i32 0) ret i32 0 } declare void @_lfortran_printf(i8*, ...) declare void @exit(i32) ``` We need to fix it: [Implement nonzero exit code and `quiet` in STOP (#597) · Issues · lfortran / lfortran · GitLab](https://gitlab.com/lfortran/lfortran/-/issues/597)