Clarify that it is recursive read locks on the read-write lock
that make it difficult to implement
PTHREAD_RWLOCK_PREFER_WRITER_NP.
Update the libc-alpha URL and provide the URL to the POSIX wording
that is quoted in the comment.
Reported-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Carlos O'Donell <carlos@redhat.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Change '--' to '\-\-' for options and '--' between words to '\(em'
(em-dash).
Signed-off-by: Bjarni Ingi Gislason <bjarniig@rhi.hi.is>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Change '-' to '\-' for the prefix of names to indicate an option.
Signed-off-by: Bjarni Ingi Gislason <bjarniig@rhi.hi.is>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
The host ID might once have been intended to be globally unique,
but that turned out not to feasible.
Reported-by: Rich Felker <dalias@libc.org>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Remove superfluous paragraph macros.
Remove request ".br" if it precedes a line, that begins with a
space, as such lines automatically cause a break.
There is no change in the output from "nroff" and "groff".
###
Examples of warnings from "mandoc -Tlint":
mandoc: bindresvport.3:41:2: WARNING: skipping paragraph macro: PP after SH
mandoc: crypt.3:228:2: WARNING: skipping paragraph macro: PP empty
mandoc: dlinfo.3:151:2: WARNING: skipping paragraph macro: IP empty
mandoc: exec.3:86:2: WARNING: skipping paragraph macro: PP after SS
mandoc: getsubopt.3:45:2: WARNING: skipping paragraph macro: br before text line with leading blank
Signed-off-by: Bjarni Ingi Gislason <bjarniig@rhi.hi.is>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
These are all links that were created several years ago, mainly
when pages were migrated to different sections, in order to
allow the 'man' commands using the old section numbers to work.
However, the plan was always to eventually remove them, after
allowing people who cared to get used to the new section numbers.
Now, after 5+ years in each case, it's time to remove
these links.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
I believe new users should be discouraged from using atoi() and
that its disadvantages should be explained.
I added the information that 0 is returned on error - although C
standard and POSIX say that "If the value of the result cannot be
represented, the behavior is undefined." there are some
interpretations that 0 has to be returned
https://stackoverflow.com/questions/38393162/what-can-i-assume-about-the-behaviour-of-atoi-on-error
and this is also what happens in practice with glibc, musl and
uClibc.
Signed-off-by: Arkadiusz Drabczyk <arkadiusz@drabczyk.org>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Output is from: test-groff -b -e -mandoc -T utf8 -rF0 -t -w w -z
[ "test-groff" is a developmental version of "groff" ]
There is no change in the output of "nroff" and "groff".
####
troff: <fts.3>:50: warning: trailing space
####
troff: <getgrnam.3>:175: warning: trailing space
####
troff: <getpwnam.3>:181: warning: trailing space
####
troff: <rcmd.3>:52: warning: trailing space
troff: <rcmd.3>:57: warning: trailing space
troff: <rcmd.3>:60: warning: trailing space
troff: <rcmd.3>:63: warning: trailing space
troff: <rcmd.3>:69: warning: trailing space
troff: <rcmd.3>:73: warning: trailing space
####
troff: <rexec.3>:48: warning: trailing space
troff: <rexec.3>:51: warning: trailing space
####
troff: <sem_open.3>:36: warning: trailing space
Signed-off-by: Bjarni Ingi Gislason <bjarniig@rhi.hi.is>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
RAND_MAX is for rand(3). POSIX fixes random()'s range at 2^31-1;
RAND_MAX may be smaller on some platforms (even though with glibc
or musl on Linux they are the same).
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
In the few pages where this heading (which is "nonstandard" within
man-pages) is used, it always immediately follows CONFORMING TO
and generally contains information related to standards. Remove
the section heading, thus incorporating AVAILABILITY into
CONFORMING TO.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
EXAMPLES appears to be the wider majority usage across various
projects' manual pages, and is also what is used in the POSIX
manual pages.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
The fact that an FE_UNDERFLOW exception is not raised for
"Range error: result underflow" is intended behavior.
See https://www.sourceware.org/bugzilla/show_bug.cgi?id=6806.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
The function make_message illustrates how to use vsnprintf to
determine the required amount of memory for a specific format and
its arguments.
If make_message is called with a format which will use exactly
INT_MAX characters (excluding '\0'), then the size++ calculation
will overflow the signed integer "size", which is an undefined
behaviour in C.
Since malloc and vsnprintf rightfully take a size_t argument, I
decided to use a size_t variable for size calculation. Therefore,
this patched code uses variables of the same data types as
expected by function arguments.
Proof of concept (tested on Linux/glibc amd64):
int main() { make_message("%647s%2147483000s", "", ""); }
If the code is compiled with address sanitizer (gcc
-fsanitize=address) you can see the following line, assuming that
a signed integer overflow simply leads to INT_MIN:
==3094==WARNING: AddressSanitizer failed to allocate 0xffffffff80000000 bytes
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Carlos O'Donell