In the RETURN VALUE sections, a number of different wordings
are used in to describe the fact that 'errno' is set on error.
There's no reason for the difference in wordings, since the same
thing is being described in each case. Switch to a standard
wording that is the same as FreeBSD and similar to the wording
used in POSIX.1.
In this change, fix some instances stating that 'errno' is set
"appropriately" to instead say "to indicate the error".
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
In the RETURN VALUE sections, a number of different wordings
are used in to describe the fact that 'errno' is set on error.
There's no reason for the difference in wordings, since the same
thing is being described in each case. Switch to a standard
wording that is the same as FreeBSD and similar to the wording
used in POSIX.1.
In this change, "to indicate the cause of the error"
is changed to "to indicate the error".
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
The current mark-up renders poorly. To resolve this, move
the type information into a separate line.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Since we are using .nf/.fi to bracket FTM info, escaping
space characters serves no space and clutters the source.
Reported-by: Alejandro Colomar (man-pages) <alx.manpages@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Make the formatting more consistent inside the tables in the
ATTRIBUTES sections. Make the source code more uniform; in
particular, eliminate the use of custom tweaks using
'lbwNN'/'lwNN' and .br macros. In addition, ensure that
hyphenation and text justification do not occur inside the tables.
This is a script-driven edit:
[[
PAGE_LIST=$(git grep -l 'SH ATTRIBUTES' man[23])
# Strip out any preexisting .sp/.br/.ad macros
sed -i '/SH ATTR/,/^\.SH/{/^\.sp/d; /^\.br/d; /\.ad/d}' $PAGE_LIST
# Eliminate any use of 'wNN' in tables; default first column
# to fill unused space
sed -i '/SH ATTR/,/^\.SH/s/lbw[0-9]*/lb/g' $PAGE_LIST
sed -i '/SH ATTR/,/^\.SH/s/lw[0-9]*/l/g' $PAGE_LIST
sed -i '/SH ATTR/,/^\.SH/s/^lb /lbx /' $PAGE_LIST
# Nest the tables inside ".ad l"+".nh" and ".hy"+".ad"+".sp 1"
# ".ad l" ==> no right justification of text in table cells
# ".nh" ==> No hyphenation in table cells
# ".sp 1" ==> ensure a blank line before the next section heading
sed -i '/SH ATTR/,/^\.SH/{/\.TS/i.ad l\n.nh
}' $PAGE_LIST
sed -i '/SH ATTR/,/^\.SH/{/\.TE/a.hy\n.ad\n.sp 1
}' $PAGE_LIST
# In a few of the tables, the third column has a lot of text, so
# make that column wide (rather than the first column)
sed -i '/^lbx/{s/lbx/lb/;s/lb$/lbx/}' \
man3/bindresvport.3 \
man3/fmtmsg.3 man3/gethostbyname.3 man3/getlogin.3 \
man3/getnetent.3 man3/getprotoent.3 man3/getpwent.3 \
man3/getservent.3 man3/getspnam.3 man3/getutent.3 man3/glob.3 \
man3/login.3 \
man3/setnetgrent.3 \
man3/wordexp.3
]]
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
In the SYNOPSIS, a long function prototype may need to be
continued over to the next line. The continuation line is
indented according to the following rules:
1. If there is a single such prototype that needs to be continued,
then align the continuation line so that when the page is
rendered on a fixed-width font device (e.g., on an xterm) the
continuation line starts just below the start of the argument
list in the line above. (Exception: the indentation may be
adjusted if necessary to prevent a very long continuation line
or a further continuation line where the function prototype is
very long.)
Thus:
int tcsetattr(int fd, int optional_actions,
const struct termios *termios_p);
2. But, where multiple functions in the SYNOPSIS require
continuation lines, and the function names have different
lengths, then align all continuation lines to start in the
same column. This provides a nicer rendering in PDF output
(because the SYNOPSIS uses a variable width font where
spaces render narrower than most characters).
Thus:
int getopt(int argc, char * const argv[],
const char *optstring);
int getopt_long(int argc, char * const argv[],
const char *optstring,
const struct option *longopts, int *longindex);
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Since _BSD_SOURCE is obsolete for quite some time now,
it should not be listed as the first FTM for lstat().
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Generally, place '||' at start of a line, rather than the end of
the previous line.
Rationale: this placement clearly indicates that that each piece
is an alternative.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Different source styles are used in different pages to achieve the
same formatted output, and in some cases the source mark-up is a
rather convoluted combination of .RS/.RE/.TP/.PD macros. Simplify
this greatly, and unify all of the pages to use more or less the
same source code style. This makes the source code rather easier
to read, and may simplify future scripted global changes.
The feature test macro info is currently bracketed by .nf/.fi
pairs. This is not strictly necessary (i.e., it makes no
difference to the rendered output), but for the moment we keep
these "brackets" in case they may be replaced with something else.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
The majority of pages use .nf/.fi in SYNOPSIS, but there are
still many that don't and use .br to achieve newlines. Fix many
of those. This brings greater consistency to the pages, which
eases editing and may ease future scripted edits to the pages.
Many of these changes were script-assisted, with some additional
manual edits.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Yet more clean-ups after commit
15d6565317.
Reported-by: Alejandro Colomar (man-pages) <alx.manpages@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Since glibc 2.29, there is a wrapper for getcpu(2).
The wrapper has only 2 arguments, omitting the unused
third system call argument. Rework the manual page
to reflect this.
Reported-by: Alejandro Colomar <alx.manpages@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Most pages use 'unsigned int' (and the kernel too).
Make them all do so.
$ find man? -type f \
| xargs sed -i \
-e 's/unsigned \*/unsigned int */g'
-e 's/unsigned "/unsigned int "/g';
Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
The use of vertical white space in the SYNOPSIS sections
is rather inconsistent. Make it more consistent, subject to the
following heuristics:
* Prefer no blank lines between function signatures by default.
* Where many functions are defined in the SYNOPSIS, add blank
lines where needed to improve readability, possibly by using
blank lines to separate logical groups of functions.
Reported-by: Alejandro Colomar (man-pages) <alx.manpages@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Bring a bit more consistency to Feature Test Macro information
(mainly .PP between differnt FTM lists).
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Use .PP (which gives a bit of vertical white space) rather than
.br to separate functions in Feature Test Macro requirement lists.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
The Linux kernel uses 'unsigned int' instead of 'int' for the
'flags' parameter. As glibc provides no wrapper, use the same
type the kernel uses.
......
$ syscall='delete_module';
$ find linux/ -type f -name '*.c' \
|xargs pcregrep -Mn "(?s)^[\w_]*SYSCALL_DEFINE.\(${syscall},.*?\)";
linux/kernel/module.c:977:
SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
unsigned int, flags)
Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
See previous commit.
This commit normalizes texts under sections other than SYNOPSIS
(most of them in NOTES).
Signed-off-by: Ganimedes Colomar <gacoan.linux@gmail.com>
Cowritten-by: Alejandro Colomar <alx.manpages@gmail.com>
Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
To easily distinguish documentation about glibc wrappers from
documentation about kernel syscalls, let's have a normalized
'Note' in the SYNOPSIS, and a further explanation in the page body
(NOTES in most of them), as already happened in many (but not all)
of the manual pages for syscalls without a wrapper. Furthermore,
let's normalize the messages, following membarrier.2 (because it's
already quite extended), so that it's easy to use grep to find
those pages.
To find these pages, we used:
$ grep -rn wrapper man? | sort -V
and
$ grep -rni support.*glibc | sort -V
delete_module.2, init_module.2: glibc 2.23 is no longer
maintained, so we changed the notes about wrappers, to say that
there are no glibc wrappers for these system calls; see NOTES.
We didn't fix some obsolete pages such as create_module.2.
Signed-off-by: Ganimedes Colomar <gacoan.linux@gmail.com>
Cowritten-by: Alejandro Colomar <alx.manpages@gmail.com>
Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Rationale:
$ man 7 man-pages 2>/dev/null | sed -n /Paragraphs/,/^$/p
Paragraphs should be separated by suitable markers (usually
either .PP or .IP). Do not separate paragraphs using blank
lines, as this results in poor rendering in some output
formats (such as PostScript and PDF).
Fix:
$ sed -i -e '1,/^\.EX/s/^$/.PP/' -e '/^\.EE/,/^\.EX/s/^$/.PP/' man?/*
And then some manual adjustments.
Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
I noticed this while working on some silly "hello, world"
programs, see https://git.sr.ht/~phf/hello-again if you're
curious. Disassembling sh4 code showed trap #31 all over the
place but the syscall(2) man page talked about trap #0x17 and
friends. Checking the kernel sources I got lucky in
arch/sh/kernel/entry-common.S where in commit 3623d138213ae Rich
Felker clarifies the situation.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Reported-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com>
Cc: Martin Sebor <msebor@redhat.com>
Cc: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
The Linux kernel uses 'int' instead of 'long' for the return type.
As glibc provides no wrapper, use the same type the kernel uses.
......
$ grep -n wrapper man-pages/man2/subpage_prot.2
40:There is no glibc wrapper for this system call; see NOTES.
99:Glibc does not provide a wrapper for this system call; call it using
$ grep -rn SYSCALL_DEFINE.*subpage_prot linux/;
linux/arch/powerpc/mm/book3s64/subpage_prot.c:190:
SYSCALL_DEFINE3(subpage_prot, unsigned long, addr,
$ sed -n /SYSCALL.*subpage_prot/,/^}/p \
linux/arch/powerpc/mm/book3s64/subpage_prot.c \
|grep return;
return -ENOENT;
return -EINVAL;
return -EINVAL;
return 0;
return -EFAULT;
return -EFAULT;
return err;
$ sed -n /SYSCALL.*subpage_prot/,/^}/p \
linux/arch/powerpc/mm/book3s64/subpage_prot.c \
|grep '\<err\>';
int err;
err = -ENOMEM;
err = -ENOMEM;
err = 0;
return err;
Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
This paragraph is a little bit hidden at the end of DESCRIPTION;
make it a little more prominent.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Linux kernel commit aae8a97d3ec30788790d1720b71d76fd8eb44b73 (part
of kernel release v2.6.39) added a check to disallow creating a
hardlink to an unlinked file.
The manual page already describes the trick of using
AT_SYMLINK_FOLLOW as an alternative to AT_EMPTY_PATH, and for
AT_EMPTY_PATH the manual page already notes that it "will
generally not work if the file has a link count of zero". However,
the precise error (ENOENT) is not mentioned, and the error case
isn't mentioned in the ERRORS section at all.
This makes it easy to overlook the fact that the AT_SYMLINK_FOLLOW
trick on /proc/self/fd/NN won't work on deleted files, as
evidenced by the follow message (which turns up when googling
"linkat deleted ENOENT"):
https://groups.google.com/g/linux.kernel/c/zZO4lqqwp64
Signed-off-by: Mathias Rav <m@git.strova.dk>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
The Linux kernel uses 'pid_t' instead of 'long' for the return type.
As glibc provides no wrapper, use the same types the kernel uses.
$ sed -n 34,36p man-pages/man2/set_tid_address.2
.PP
.IR Note :
There is no glibc wrapper for this system call; see NOTES.
$ grep -rn 'SYSCALL_DEFINE.*set_tid_address' linux/
linux/kernel/fork.c:1632:
SYSCALL_DEFINE1(set_tid_address, int __user *, tidptr)
$ sed -n 1632,1638p linux/kernel/fork.c
SYSCALL_DEFINE1(set_tid_address, int __user *, tidptr)
{
current->clear_child_tid = tidptr;
return task_pid_vnr(current);
}
$ grep -rn 'task_pid_vnr(struct' linux/
linux/include/linux/sched.h:1374:
static inline pid_t task_pid_vnr(struct task_struct *tsk)
Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
{.IR var [x]} -> {.I var[x]}
There were around 15 entries of the former,
and around 360 of the latter.
Found using:
$ grep -rn '^\.I[ |R].* \[.*\]' |sort
Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
In the comment of the example program, the peer blocks on fwait()
rather than fpost().
Signed-off-by: Jing Peng <pj.hades@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
With this change, there remain almost no vestiges of information
about the long defunct Linux libc.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
faccessat2() was added in Linux 5.8 and enables a fix to
longstanding bugs in the faccessat() wrapper function.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
The include path is linux/openat2, so fix the manual to reference
this correct path.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
The Linux kernel uses a long as the return type for this syscall.
As glibc provides no wrapper, use the same types the kernel uses.
Signed-off-by: Alejandro Colomar <colomar.6.4.3@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
In the kernel sources (kernel/fork.c::copy_process()), we have:
/*
* sigaltstack should be cleared when sharing the same VM
*/
if ((clone_flags & (CLONE_VM|CLONE_VFORK)) == CLONE_VM)
sas_ss_reset(p);
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
See https://bugzilla.kernel.org/show_bug.cgi?id=12665.
The fix by Thomas Gleixner was in kernel commit
78c9c4dfbf8c04883941445a195276bb4bb92c76.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Linux kernel commit 2a36ab717e8fe678d98f81c14a0b124712719840
(part of 5.10 release) changed sys_membarrier prototype/parameters
and added two new commands [MEMBARRIER_CMD_PRIVATE_EXPEDITED_RSEQ
and MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED_RSEQ]. This
man-pages patch reflects these changes, by mostly copying comments
from the kernel patch into the man-page ([Peter Oskolkov] was also
the author of the kernel change).
[mtk: commit message tweaked]
Signed-off-by: Peter Oskolkov <posk@google.com>
Cowritten-by: Alejandro Colomar <colomar.6.4.3@gmail.com>
Signed-off-by: Alejandro Colomar <colomar.6.4.3@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Linux uses aio_context_t for these syscalls,
and it's the type provided by <linux/aio_abi.h>.
Use it in the SYNOPSIS.
libaio uses 'io_context_t', but that difference is already noted
in NOTES.
[mtk: patch slightly tweaked]
Signed-off-by: Alejandro Colomar <colomar.6.4.3@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
The Linux kernel uses long as the return type for this syscall.
As glibc provides no wrapper, use the same type the kernel uses.
Signed-off-by: Alejandro Colomar <colomar.6.4.3@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
That comment wrapped on an 80-column terminal.
Divide it into two lines.
Signed-off-by: Alejandro Colomar <colomar.6.4.3@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
The Linux kernel uses the following:
kernel/futex.c:3778:
SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val,
struct __kernel_timespec __user *, utime, u32 __user *, uaddr2,
u32, val3)
Since there is no glibc wrapper, use the same types the kernel uses.
Signed-off-by: Alejandro Colomar <colomar.6.4.3@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
[mtk: Applied patch manually]
getdents():
This function has no glibc wrapper.
As such, we should use the same types the Linux kernel uses:
Use 'long' as the return type.
getdents64():
The glibc wrapper uses:
ssize_t getdents64(int, void *, size_t);
Signed-off-by: Alejandro Colomar <colomar.6.4.3@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
The text in NOTES doesn't really relate specifically to
the #include, so remove the comment on the #include.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Extend this page with the information about CAP_PERFMON capability
designed to secure performance monitoring and observability
operation in a system according to the principle of least
privilege [1] (POSIX IEEE 1003.1e, 2.2.2.39).
[1] https://sites.google.com/site/fullycapable/, posix_1003.1e-990310.pdf
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Time namespaces were added in kernel 5.6, but setns() support
for time namespaces was added only starting with kernel 5.8:
commit 76c12881a38aaa83e1eb4ce2fada36c3a732bad4
Author: Christian Brauner <christian.brauner@ubuntu.com>
Date: Mon Jul 6 17:49:11 2020 +0200
nsproxy: support CLONE_NEWTIME with setns()
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Highlight to the reader that if another filter returns a
higher-precedence action value, then the ptracer will not
be notified.
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Due to a userspace breakage, commit 1251201c0d34 ("sched/core: Fix
uclamp ABI bug, clean up and robustify sched_read_attr() ABI logic
and code") changed the semantics of sched_getattr(2) when the
userspace struct is smaller than the kernel struct. Now, any
trailing non-zero data in the kernel structure is ignored when
copying to userspace. We also document the original error code
correctly (it was EFBIG not E2BIG) in the BUGS section.
Ref: 1251201c0d34 ("sched/core: Fix uclamp ABI bug, clean up and
robustify sched_read_attr() ABI logic and code")
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Around the text:
"Feature Test Macro Requirements for glibc..."
replace ".in -4n/.in" with ".RS -4/.RE".
The latter form is more idiomatic use of man macros.
The nroff output is unchanged.
Reported-by: G. Branden Robinson <g.branden.robinson@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
From the email discussion:
> Hi Alex,
>
> On 9/25/20 9:31 AM, Alejandro Colomar wrote:
>> Signed-off-by: Alejandro Colomar <colomar.6.4.3@gmail.com>
>> ---
>> man2/seccomp.2 | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/man2/seccomp.2 b/man2/seccomp.2
>> index 58033da1c..d6b856c32 100644
>> --- a/man2/seccomp.2
>> +++ b/man2/seccomp.2
>> @@ -1101,7 +1101,7 @@ install_filter(int syscall_nr, int t_arch, int f_errno)
>> };
>>
>> struct sock_fprog prog = {
>> - .len = (unsigned short) (sizeof(filter) / sizeof(filter[0])),
>> + .len = sizeof(filter) / sizeof(filter[0]),
>> .filter = filter,
>> };
>
> I have a small doubt about this change. With the change,
> there are no compilation warnings.
>
> But, if we change the code to something slightly different:
>
> [[
> size_t x = (sizeof(filter) / sizeof(filter[0]));
> struct sock_fprog prog = {
> .len = x,
> .filter = filter,
> };
> ]]
>
> The "cc -Wconversion" gives us the following warning:
>
> warning: conversion from ‘size_t’ {aka ‘long unsigned int’}
> to ‘short unsigned int’ may change value
>
> Presumably we don't get a warning for an assignment of the form
>
> .len = (sizeof(filter) / sizeof(filter[0]))
>
> because the compiler is smart enough to work out that the
> value of the constant expression is within the range of
> "unsigned short".
>
> Your thoughts?
Hi Michael,
I'd say that the cast doesn't fix any problems at all. It silences a
valid warning, and I'd use a pragma for that (to be more explicit about
the intention of silencing a warning) if I do want -Wconversion enabled
(which usually I don't want, because it's too noisy) and I'm sure that
this won't overflow. I'd limit the use casts to only when I *really*
need to.
I guess that if you enable -O3, the warning will vanish again because
the compiler will optimize away 'x' (but I didn't test).
Signed-off-by: Alejandro Colomar <colomar.6.4.3@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Use \(aq to get an unslanted single quote inside monospace code
blocks. Using a simple ' results in a slanted quote inside PDFs.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
These variables are either of an unsigned integer type per POSIX;
or of an integer type per POSIX, that Linux defines as an unsigned integer type.
Print them with 'uintmax_t' instead of 'intmax_t' to avoid
big positive numbers being printed as negative numbers.
Bug report:
From: Konstantin Bukin @ 2020-09-13 15:04 UTC
To: mtk.manpages; +Cc: Konstantin Bukin, linux-man
inode numbers are expected to be positive. Casting them to a signed type
may result in printing negative values. E.g. running example program on
the following file:
$ ls -li test.txt
9280843260537405888 -r--r--r-- 1 kbukin hardware 300 Jul 21 06:36 test.txt
results in the following output:
$ ./example test.txt
ID of containing device: [0,480]
File type: regular file
I-node number: -9165900813172145728
Mode: 100444 (octal)
Link count: 1
Ownership: UID=2743 GID=30
Preferred I/O block size: 32768 bytes
File size: 300 bytes
Blocks allocated: 8
Last status change: Tue Jul 21 06:36:50 2020
Last file access: Sat Sep 12 14:13:38 2020
Last file modification: Tue Jul 21 06:36:50 2020
Such erroneous reporting happens for inode values greater than maximum
value which can be stored in signed long. Casting does not seem to be
necessary here. Printing inode as unsigned long fixes the issue.
Reported-by: Konstantin Bukin <kbukin@gmail.com>
Signed-off-by: Alejandro Colomar <colomar.6.4.3@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Various ports that had their own indigenous system calls have
been discontinued. Remove those system calls (none of which had
manual pages!) to a separate part of the page, to avoid
cluttering the main list of system calls.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Some of the links removed in commit 247c654385 should
have been kept, because in some cases there are real system
calls whose wrapper functions are documented in Section 3.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Let's move to the 21st century. Instead of casting system data
types to long/long long/etc. in printf() calls, instead cast to
intmax_t or uintmax_t, the largest available signed/unsigned
integer types.
[mtk: rewrote commit message]
Signed-off-by: Alejandro Colomar <colomar.6.4.3@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Use printf()'s '#' flag character to prepend the string "0x".
However, when the number is printed in uppercase, and the prefix
is in lowercase, the string "0x" needs to be manually written.
Signed-off-by: Alejandro Colomar <colomar.6.4.3@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
For consistency.
The types are written both with and without the redundant 'int' keyword
all over the man-pages. However, the most used form, by far, is the one
without 'int'.
Signed-off-by: Alejandro Colomar <colomar.6.4.3@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Notes: I copied .nf and .fi from futex.2, but they made no visual difference.
What do they actually do?
Signed-off-by: Alejandro Colomar <colomar.6.4.3@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
When calling msgrcv() with the MSG_COPY flag, it will report
EINVAL error even we if have disabled CONFIG_CHECKPOINT_RESTORE.
ENOSYS will be reported only if we also specify the IPC_NOWAIT
flag.
[mtk: edited commit message]
Notes from mtk:
The relevant kernel code is this:
[[
#ifdef CONFIG_CHECKPOINT_RESTORE
...
#else
static inline struct msg_msg *prepare_copy(void __user *buf, size_t bufsz)
{
return ERR_PTR(-ENOSYS);
}
...
static long do_msgrcv(int msqid, void __user *buf, size_t bufsz, long
msgtyp, int msgflg,
long (*msg_handler)(void __user *, struct msg_msg *, size_t))
{
...
if (msgflg & MSG_COPY) {
if ((msgflg & MSG_EXCEPT) || !(msgflg & IPC_NOWAIT))
return -EINVAL;
copy = prepare_copy(buf, min_t(size_t, bufsz, ns->msg_ctlmax));
...
}
]]
We'll only hit the ENOSYS error if:
(1) MSG_COPY was specified;
(2) IPC_NOWAIT was not specified; and
(3) CONFIG_CHECKPOINT_RESTORE was not enabled.
Signed-off-by: Yang Xu <xuyang2018.jy@cn.fujitsu.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
The type `struct msgbuf *` is implicitly casted to `const void *`.
Not only that, but the explicit cast to `void *` was slightly
misleading.
Explicitly casting can silence warnings when mistakes are made, so it's
better to remove those casts when possible.
Signed-off-by: Alejandro Colomar <colomar.6.4.3@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Rather than:
sometype x;
for (x = ....; ...)
use
for (sometype x = ...; ...)
This brings the declaration and use closer together (thus aiding
readability) and also clearly indicates the scope of the loop
counter variable.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
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@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
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@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
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@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
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@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
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@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
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@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
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@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Document fanotify_init(2) flag FAN_REPORT_NAME and the format of
the event info type FAN_EVENT_INFO_TYPE_DFID_NAME.
The fanotify_fid.c example is extended to also report the name of
the created file or subdirectory.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Matthew Bobrowski <mbobrowski@mbobrowski.org>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Document fanotify_init(2) flag FAN_REPORT_DIR_FID and event info
type FAN_EVENT_INFO_TYPE_DFID.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Matthew Bobrowski <mbobrowski@mbobrowski.org>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
With fanotify_init(2) flag FAN_REPORT_FID, the group identifies
filesystem objects by file handles in a single event info record
of type FAN_EVENT_INFO_TYPE_FID.
We intend to add support for new fanotify_init(2) flags for which
the group identifies filesystem objects by file handles and add
more event info record types.
To that end, start by changing the language of the man page to
refer to a "group that identifies filesystem objects by file
handles" instead of referring to the FAN_REPORT_FID flag and
document the extended event format structure in a more generic
manner that allows more than a single event info record and not
only a record of type FAN_EVENT_INFO_TYPE_FID.
Clarify that the object identified by the file handle refers to
the directory in directory entry modification events.
Remove a note about directory entry modification events and
monitoring a mount point that I found to be too confusing and out
of context.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Matthew Bobrowski <mbobrowski@mbobrowski.org>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Use 'struct timespec', not 'struct timeval', and adjust
the variable name accordingly.
Reported-by: Tony May <tony.may@mediakind.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Killing a thread with SECCOMP_RET_KILL_THREAD is very likely
to leave the rest of the process in a broken state.
Wording pretty much taken from Rick Felker's suggestion.
Reported-by: Rich Felker <dalias@libc.org>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
A naked tilde ("~") renders poorly in PDF. Instead use "\(ti",
which renders better in a PDF, and produces the same glyph
when rendering on a terminal.
Reported-by: Geoff Clare <gwc@opengroup.org>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Historically, a comment of the following form at the top of a
manual page was used to indicate too man(1) that the use of tbl(1)
was required in order to process tables:
'\" t
However, at least as far back as 2001 (according to Branden),
man-db's man(1) automatically uses tbl(1) as needed, rendering
this comment unnecessary. And indeed many existing pages in
man-pages that have tables don't have this comment at the top of
the file. So, drop the comment from those files where it is
present.
[mtk: completely rewrote commit message]
Reported-by: G. Branden Robinson <g.branden.robinson@gmail.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Add some paragraph breaks to the discussion of 'mode' to make
the details a bit easier to read.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
The \" comment produces blank lines. Use the .\" that the vast
majority of the codebase uses instead.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Michael Kerrisk