Hello Alex, On 9/4/20 12:21 PM, Alejandro Colomar wrote: >>From 5399e0a620c417c1003c17fb04a45ce1a7854acd Mon Sep 17 00:00:00 2001 > From: Alejandro Colomar <colomar.6.4.3@xxxxxxxxx> > Date: Thu, 3 Sep 2020 21:25:59 +0200 > Subject: [PATCH 03/34] eventfd.2: Use sizeof consistently > > Use ``sizeof`` consistently through all the examples in the following > way: > > - Use the name of the variable instead of its type as argument for > ``sizeof``. > > Rationale: > https://www.kernel.org/doc/html/v5.8/process/coding-style.html#allocating-memory > > Signed-off-by: Alejandro Colomar <colomar.6.4.3@xxxxxxxxx> > --- > man2/eventfd.2 | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/man2/eventfd.2 b/man2/eventfd.2 > index 804cf796b..35e83c957 100644 > --- a/man2/eventfd.2 > +++ b/man2/eventfd.2 > @@ -415,8 +415,8 @@ main(int argc, char *argv[]) > printf("Child writing %s to efd\en", argv[j]); > u = strtoull(argv[j], NULL, 0); > /* strtoull() allows various bases */ > - s = write(efd, &u, sizeof(uint64_t)); > - if (s != sizeof(uint64_t)) > + s = write(efd, &u, sizeof(u)); > + if (s != sizeof(u)) > handle_error("write"); > } > printf("Child completed write loop\en"); > @@ -427,8 +427,8 @@ main(int argc, char *argv[]) > sleep(2); > > printf("Parent about to read\en"); > - s = read(efd, &u, sizeof(uint64_t)); > - if (s != sizeof(uint64_t)) > + s = read(efd, &u, sizeof(u)); > + if (s != sizeof(u)) > handle_error("read"); > printf("Parent read %llu (0x%llx) from efd\en", > (unsigned long long) u, (unsigned long long) u); > This is an example where I am dubious that the change is a good idea. For this API, the units that are being read/written really *must* be 8-byte integers (it's baked into the API), and I feel that explicitly mentioning the types in the example code reinforces that point. For the moment, I won't apply this patch. Cheers, Michael -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ Linux/UNIX System Programming Training: http://man7.org/training/
