* [patch] getgrouplist.3: tfix in example @ 2024-03-06 16:13 Fedor Lapshin 2024-03-16 0:27 ` Alejandro Colomar 0 siblings, 1 reply; 5+ messages in thread From: Fedor Lapshin @ 2024-03-06 16:13 UTC (permalink / raw) To: alx; +Cc: linux-man In example of getgrouplist, if getpwnam returns NULL, the program exits. The exit code EXIT_SUCCESS looks like a mistake, since the program also calls perror right before. This patch changes the exit code to EXIT_FAILURE. Best regards, Fedor. --- man3/getgrouplist.3 | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/man3/getgrouplist.3 b/man3/getgrouplist.3 index 41389b6c3..239913ce6 100644 --- a/man3/getgrouplist.3 +++ b/man3/getgrouplist.3 @@ -165,7 +165,7 @@ main(int argc, char *argv[]) pw = getpwnam(argv[1]); if (pw == NULL) { perror("getpwnam"); - exit(EXIT_SUCCESS); + exit(EXIT_FAILURE); } \& /* Retrieve group list. */ -- 2.34.1 ^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [patch] getgrouplist.3: tfix in example 2024-03-06 16:13 [patch] getgrouplist.3: tfix in example Fedor Lapshin @ 2024-03-16 0:27 ` Alejandro Colomar 2024-03-27 19:20 ` [PATCH] getgrouplist.3: EXAMPLES: fix error handling for getpwnam(3) Fedor Lapshin 0 siblings, 1 reply; 5+ messages in thread From: Alejandro Colomar @ 2024-03-16 0:27 UTC (permalink / raw) To: Fedor Lapshin; +Cc: linux-man [-- Attachment #1: Type: text/plain, Size: 2357 bytes --] Hi Fedor, On Wed, Mar 06, 2024 at 07:13:31PM +0300, Fedor Lapshin wrote: > In example of getgrouplist, if getpwnam returns NULL, the program > exits. The exit code EXIT_SUCCESS looks like a mistake, since the > program also calls perror right before. > > This patch changes the exit code to EXIT_FAILURE. While your patch seems correct, it's not the only problem I see with this call to getpwnam(3): it should clear errno before the call, since a return of NULL doesn't necessarily mean an error. See getpwnam(3): $ MANWIDTH=72 man getpwnam | sed -n '/^RETURN/,/^$/p' RETURN VALUE The getpwnam() and getpwuid() functions return a pointer to a passwd structure, or NULL if the matching entry is not found or an error occurs. If an error occurs, errno is set to indicate the error. If one wants to check errno after the call, it should be set to zero before the call. So I would also add 'errno = 0;' before the call, and then name the commit something like getgrouplist.3: EXAMPLES: Fix error handling after getpwnam(3) > > Best regards, Fedor. Would you mind signing the patch? See <./CONTRIBUTING.d/patches>: - Sign your patch with "Signed-off-by:". Read about the "Developer's Certificate of Origin" at <https://www.kernel.org/doc/Documentation/process/submitting-patches.rst>. When appropriate, other tags documented in that file, such as "Reported-by:", "Reviewed-by:", "Acked-by:", and "Suggested-by:" can be added to the patch. The man-pages project also uses a "Cowritten-by:" tag with the obvious meaning. Example: Signed-off-by: Alejandro Colomar <alx@kernel.org> Have a lovely night! Alex > --- > man3/getgrouplist.3 | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/man3/getgrouplist.3 b/man3/getgrouplist.3 > index 41389b6c3..239913ce6 100644 > --- a/man3/getgrouplist.3 > +++ b/man3/getgrouplist.3 > @@ -165,7 +165,7 @@ main(int argc, char *argv[]) > pw = getpwnam(argv[1]); > if (pw == NULL) { > perror("getpwnam"); > - exit(EXIT_SUCCESS); > + exit(EXIT_FAILURE); > } > \& > /* Retrieve group list. */ > -- > 2.34.1 -- <https://www.alejandro-colomar.es/> [-- Attachment #2: signature.asc --] [-- Type: application/pgp-signature, Size: 833 bytes --] ^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH] getgrouplist.3: EXAMPLES: fix error handling for getpwnam(3) 2024-03-16 0:27 ` Alejandro Colomar @ 2024-03-27 19:20 ` Fedor Lapshin 2024-03-27 19:23 ` Fedor Lapshin 0 siblings, 1 reply; 5+ messages in thread From: Fedor Lapshin @ 2024-03-27 19:20 UTC (permalink / raw) To: Alejandro Colomar; +Cc: linux-man Signed-off-by: Fedor Lapshin <fe.lap.prog@gmail.com> --- man3/getgrouplist.3 | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/man3/getgrouplist.3 b/man3/getgrouplist.3 index 41389b6c3..cf23dfa78 100644 --- a/man3/getgrouplist.3 +++ b/man3/getgrouplist.3 @@ -162,10 +162,11 @@ main(int argc, char *argv[]) \& /* Fetch passwd structure (contains first group ID for user). */ \& + errno = 0; pw = getpwnam(argv[1]); if (pw == NULL) { perror("getpwnam"); - exit(EXIT_SUCCESS); + exit(EXIT_FAILURE); } \& /* Retrieve group list. */ -- 2.34.1 ^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH] getgrouplist.3: EXAMPLES: fix error handling for getpwnam(3) 2024-03-27 19:20 ` [PATCH] getgrouplist.3: EXAMPLES: fix error handling for getpwnam(3) Fedor Lapshin @ 2024-03-27 19:23 ` Fedor Lapshin 2024-03-27 20:14 ` Alejandro Colomar 0 siblings, 1 reply; 5+ messages in thread From: Fedor Lapshin @ 2024-03-27 19:23 UTC (permalink / raw) To: Alejandro Colomar; +Cc: linux-man So sorry for the email to your personal email without the cc! ср, 27 мар. 2024 г. в 22:20, Fedor Lapshin <fe.lap.prog@gmail.com>: > > Signed-off-by: Fedor Lapshin <fe.lap.prog@gmail.com> > --- > man3/getgrouplist.3 | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/man3/getgrouplist.3 b/man3/getgrouplist.3 > index 41389b6c3..cf23dfa78 100644 > --- a/man3/getgrouplist.3 > +++ b/man3/getgrouplist.3 > @@ -162,10 +162,11 @@ main(int argc, char *argv[]) > \& > /* Fetch passwd structure (contains first group ID for user). */ > \& > + errno = 0; > pw = getpwnam(argv[1]); > if (pw == NULL) { > perror("getpwnam"); > - exit(EXIT_SUCCESS); > + exit(EXIT_FAILURE); > } > \& > /* Retrieve group list. */ > -- > 2.34.1 ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] getgrouplist.3: EXAMPLES: fix error handling for getpwnam(3) 2024-03-27 19:23 ` Fedor Lapshin @ 2024-03-27 20:14 ` Alejandro Colomar 0 siblings, 0 replies; 5+ messages in thread From: Alejandro Colomar @ 2024-03-27 20:14 UTC (permalink / raw) To: Fedor Lapshin; +Cc: linux-man [-- Attachment #1: Type: text/plain, Size: 1717 bytes --] Hi Fedor, On Wed, Mar 27, 2024 at 10:23:21PM +0300, Fedor Lapshin wrote: > So sorry for the email to your personal email without the cc! No problem! We humans make mistakes some times (and AIs make them all the time). ;) You can configure git to always send to me and the list for this repository. I have this in the man-pages <.git/config>, which might be useful to you: [sendemail] to = linux-man@vger.kernel.org > ср, 27 мар. 2024 г. в 22:20, Fedor Lapshin <fe.lap.prog@gmail.com>: > > > > Signed-off-by: Fedor Lapshin <fe.lap.prog@gmail.com> > > --- > > man3/getgrouplist.3 | 3 ++- > > 1 file changed, 2 insertions(+), 1 deletion(-) > > > > diff --git a/man3/getgrouplist.3 b/man3/getgrouplist.3 > > index 41389b6c3..cf23dfa78 100644 > > --- a/man3/getgrouplist.3 > > +++ b/man3/getgrouplist.3 > > @@ -162,10 +162,11 @@ main(int argc, char *argv[]) > > \& > > /* Fetch passwd structure (contains first group ID for user). */ > > \& > > + errno = 0; > > pw = getpwnam(argv[1]); > > if (pw == NULL) { > > perror("getpwnam"); > > - exit(EXIT_SUCCESS); > > + exit(EXIT_FAILURE); In case errno == NULL, there's no such user, but the call succeeded. Calling perror(3) in that case will be weird. I suggest: errno = 0; pw = getpwnam(argv[1]); if (pw == NULL) { if (errno == 0) fprintf(stderr, "'%s': No such user", argv[1]); else perror("getpwnam"); exit(EXIT_FAILURE); } Have a lovely night! Alex > > } > > \& > > /* Retrieve group list. */ > > -- > > 2.34.1 > -- <https://www.alejandro-colomar.es/> Looking for a remote C programming job at the moment. [-- Attachment #2: signature.asc --] [-- Type: application/pgp-signature, Size: 833 bytes --] ^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2024-03-27 20:14 UTC | newest] Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2024-03-06 16:13 [patch] getgrouplist.3: tfix in example Fedor Lapshin 2024-03-16 0:27 ` Alejandro Colomar 2024-03-27 19:20 ` [PATCH] getgrouplist.3: EXAMPLES: fix error handling for getpwnam(3) Fedor Lapshin 2024-03-27 19:23 ` Fedor Lapshin 2024-03-27 20:14 ` Alejandro Colomar
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