Hi Andi, On Mon, Jan 26, 2009 at 9:29 PM, Andi Kleen <andi@xxxxxxxxxxxxxx> wrote: > > While writing a little program using capset > I found the capset manpage quite light on crucial > details and I had to resort to RTFS. Yes, I've always thought that page was a little thin, but had never got to checking the details. > This patch improves the points I found unclear > and also moves one misplaced paragraph around. Thanks. I applied this for man-pages-3.18. Cheers, Michael > --- man2/capget.2-o 2009-01-26 21:19:13.000000000 +0100 > +++ man2/capget.2 2009-01-26 21:26:24.000000000 +0100 > @@ -6,6 +6,7 @@ > .\" Modified 2008-04-28, morgan of kernel.org > .\" Update in line with addition of file capabilities and > .\" 64-bit capability sets in kernel 2.6.2[45]. > +.\" Modified 2009-01-26, andi kleen > .\" > .TH CAPGET 2 2008-07-14 "Linux" "Linux Programmer's Manual" > .SH NAME > @@ -36,7 +37,8 @@ > but the kernel API is likely to change and use of > these functions (in particular the format of the > .I cap_user_*_t > -types) is subject to change with each kernel revision. > +types) is subject to extension with each kernel revision, > +but old programs will keep working. > .sp > The portable interfaces are > .BR cap_set_proc (3) > @@ -73,19 +75,19 @@ > .fi > .in -4n > .sp > -The calls will fail with the error > -.BR EINVAL , > -and set the > -.I version > -field of > -.I hdrp > -to the kernel preferred value of > -.B _LINUX_CAPABILITY_VERSION_? > -when an unsupported > -.I version > -value is specified. > -In this way, one can probe what the current > -preferred capability revision is. > +.I effective, permitted, inheritable > +are bitmasks of the capabilities defined in > +.I capability(7). > +Note the > +.I CAP_* > +defines are bit indexes and need to be shifted up before oring into > +the bitfields. > +To define the structures for passing to the syscall you have to use the > +.I struct __user_cap_header_struct > +and > +.I struct __user_cap_data_struct > +names because the typedefs are only pointers. > + > Kernels prior to 2.6.25 prefer > 32-bit capabilities with version > .BR _LINUX_CAPABILITY_VERSION_1 , > @@ -154,6 +156,20 @@ > On error, \-1 is returned, and > .I errno > is set appropriately. > + > +The calls will fail with the error > +.BR EINVAL , > +and set the > +.I version > +field of > +.I hdrp > +to the kernel preferred value of > +.B _LINUX_CAPABILITY_VERSION_? > +when an unsupported > +.I version > +value is specified. > +In this way, one can probe what the current > +preferred capability revision is. > .SH ERRORS > .TP > .B EFAULT > > -- > ak@xxxxxxxxxxxxxxx -- Speaking for myself only. > -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ git://git.kernel.org/pub/scm/docs/man-pages/man-pages.git man-pages online: http://www.kernel.org/doc/man-pages/online_pages.html Found a bug? http://www.kernel.org/doc/man-pages/reporting_bugs.html -- 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
