AMD GPUs as mentioned at: aws.amazon.com/ec2/instance-types/g4/
It's not a tree, it's actually a DAG by Ciro Santilli 35 Updated 2025-01-29 +Created 1970-01-01
Every tree is a directed acyclic graph.
But not every directed acyclic graph is a tree.
Example of a tree (and therefore also a DAG):Convention in this presentation: arrows implicitly point up, just like in a and so on.
5
|
4 7
| |
3 6
|/
2
|
1
git log
, i.e.:- 1 is parent of 2
- 2 is parent of 3 and 6
- 3 is parent of 4
Example of a DAG that is not a tree:This is not a tree because there are two ways to reach 7:
7
|\
4 6
| |
3 5
|/
2
|
1
- 2, 3, 4, 7
- 2, 5, 6, 7
But we often say "tree" intead of "DAG" in the context of Git because DAG sounds ugly.
Example of a graph that is not a DAG:This one is not acyclic because there is a cycle 2, 3, 4, 5, 2.
6
^
|
3->4
^ |
| v
2<-5
^
|
1
Stopped 2019 apparently. Shame. We need something to be upstreamed!
- source code: github.com/atrosinenko/qemujs
- demo: atrosinenko.github.io/qemujs-demo/
- demo source code: github.com/atrosinenko/qemujs-demo
In index 0,
SHT_NULL
is mandatory. Are there any other uses for it: stackoverflow.com/questions/26812142/what-is-the-use-of-the-sht-null-section-in-elf ?An ELF file contains the following parts:
- ELF header. Points to the position of the section header table and the program header table.
- Section header table (optional on executable). Each has
e_shnum
section headers, each pointing to the position of a section. - N sections, with
N <= e_shnum
(optional on executable) - Program header table (only on executable). Each has
e_phnum
program headers, each pointing to the position of a segment. - N segments, with
N <= e_phnum
(only on executable)
The order of those parts is not fixed: the only fixed thing is the ELF header that must be the first thing on the file: Generic docs say:
Although the figure shows the program header table immediately after the ELF header, and the section header table following the sections, actual files may differ. Moreover, sections and segments have no specified order. Only the ELF header has a fixed position in the file.
In pictures: sample object file with three sections:
+-------------------+
| ELF header |---+
+---------> +-------------------+ | e_shoff
| | |<--+
| Section | Section header 0 |
| | |---+ sh_offset
| Header +-------------------+ |
| | Section header 1 |---|--+ sh_offset
| Table +-------------------+ | |
| | Section header 2 |---|--|--+
+---------> +-------------------+ | | |
| Section 0 |<--+ | |
+-------------------+ | | sh_offset
| Section 1 |<-----+ |
+-------------------+ |
| Section 2 |<--------+
+-------------------+
But nothing (except sanity) prevents the following topology:
+-------------------+
| ELF header |---+ e_shoff
+-------------------+ |
| Section 1 |<--|--+
+---------> +-------------------+ | |
| | |<--+ | sh_offset
| Section | Section header 0 | |
| | |------|---------+
| Header +-------------------+ | |
| | Section header 1 |------+ |
| Table +-------------------+ |
| | Section header 2 |---+ | sh_offset
+---------> +-------------------+ | sh_offset |
| Section 2 |<--+ |
+-------------------+ |
| Section 0 |<---------------+
+-------------------+
But some newbies may prefer PNGs :-)
- Compiler toolchains generate and read ELF files.Sane compilers should use a separate standalone library to do the dirty work. E.g., Binutils uses BFD (in-tree and canonical source).
- Operating systems read and run ELF files.Kernels cannot link to a library nor use the C stlib, so they are more likely to implement it themselves.This is the case of the Linux kernel 4.2 which implements it in th file
fs/binfmt_elf.c
.
- Specialized libraries. Examples:
Ubuntu 24.04 "The application files has closed unexpectedly" by Ciro Santilli 35 Updated 2025-01-29 +Created 1970-01-01
Happens at startup without doing anything, and then keeps happening randomly infinitely many times... on a almost clean 24.04 ISO install on Dell Inspiron 15 3520... God how can it be so bad.
Viewing the apport issue a bit further shows title:
nautilus crashed with sigabrt in g_assertion_message_expr
Possibly related:
- www.reddit.com/r/Ubuntu/comments/1ce1027/2404_is_a_terrible_release/
- bugs.launchpad.net/ubuntu/+source/nautilus/+bug/1795210
- bugs.launchpad.net/ubuntu/+source/nautilus/+bug/1823529
- askubuntu.com/questions/1406294/nautilus-keeps-crashing-in-22-04
- superuser.com/questions/42068/application-are-closed-down-unexpectedly-under-ubuntu
- ubuntuforums.org/showthread.php?t=2466502
- x.com/cirosantilli/status/1792792620323967227
Pinned article: ourbigbook/introduction-to-the-ourbigbook-project
Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
We have two killer features:
- topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculusArticles of different users are sorted by upvote within each article page. This feature is a bit like:
- a Wikipedia where each user can have their own version of each article
- a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it. - local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
- to OurBigBook.com to get awesome multi-user features like topics and likes
- as HTML files to a static website, which you can host yourself for free on many external providers like GitHub Pages, and remain in full control
- Internal cross file references done right:
- Infinitely deep tables of contents:
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact