Am 23.11.2017 10:47, schrieb Michael Kerrisk (man-pages): > Hi Walter, > > On 23 November 2017 at 10:23, walter harms <wharms@xxxxxx> wrote: >> >> >> Am 23.11.2017 10:07, schrieb Michael Kerrisk (man-pages): >>> On 11/23/2017 09:31 AM, Christoph Hellwig wrote: >>>> On Wed, Nov 22, 2017 at 07:15:45PM -0500, Wesley Aptekar-Cassels wrote: >>>>> This patch documents the values of error numbers on linux. This is >>>>> something that is in the OpenBSD errno man page, which I find quite >>>>> useful. >>>> >>>> Error numbers are different for different architectures. >>> >>> I was just about to say the same. >>> >>> Someone else recently proposed the same change, and I should have >>> thought then to add the text that I have added just now to errno(3). >>> Hopefully this goes someway to addressing your requirements, Wesley. >>> >>> New text: >>> >>> On Linux, the error numbers that correspond to each symbolic name >>> vary somewhat across architectures. Therefore, numeric values are >>> not included in the list of error names below. On any particular >>> system, one can obtain a list of all symbolic error names and the >>> corresponding error numbers using the errno(1) command: >>> >> If i read this that would mean the values differ between the linux architectures only. >> I do not ting that was intended. > > Indeed. So, I changed the text to: > > The error numbers that correspond to each symbolic name vary > across UNIX systems, and even across different architectures on > Linux. Therefore, numeric values are not included in the list of > error names below. Portable applications should use the symbolic > error names (rather than explicit error numbers). The perror(3) > and strerror(3) functions can be used to convert these names to > corresponding textual error messages. > >> What about that: >> >> >> Portability: >> Programmers should use always the symbolic names as that the value of errno may vary >> across different systems. Always use strerror (3) (or compareable) to translate >> the errno code into a human readable string. >> >> note: errno (1) is a nice programm and it could be mentioned but a propper programm >> simply should not say things like "Error: 13". > > I'm not sure what you are referring to with the preceding line. > I would move the bulk of the text to a portability section or like because this is the section where i would expect that information. NTL i was not aware that different linux versions have different code for the same error that should be changed. Also i would drop "Portable" simply write "applications should use ..." there is no reason to write programms that require the numeric value. Corner cases may exists but a man page is no law, so i see no problem. just my 2 cents, re, wh > Thanks for the input, Walter. > > Cheers, > > Michael > >> re, >> wh >> >> >>> $ errno -l >>> EPERM 1 Operation not permitted >>> ENOENT 2 No such file or directory >>> ESRCH 3 No such process >>> EINTR 4 Interrupted system call >>> EIO 5 Input/output error >>> ... >>> >>> The errno(1) command can also be used to look up individual error >>> numbers and names as in the following examples: >>> >>> $ errno 2 >>> ENOENT 2 No such file or directory >>> $ errno ESRCH >>> ESRCH 3 No such process >>> >>> Cheers, >>> >>> Michael >>> > > > -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
