- Author
- Posted by mrshu, with replies from many commenters
- Published
- 16 June 2026
- Kind
- Hacker News thread on a short personal blog post
- Original
- news.ycombinator.com/item?id=48558018
- Subject
- Software tools and craft
What it is
The poster, mrshu, wrote about checking a service from a container lacking curl and wget. The thread is the post author's explanation plus a large number of comments. The linked blog post itself was not read. The poster accepts one commenter's correction and says the article will be made more precise.
What it says
- The poster says Bash has /dev/tcp, which can send the equivalent of an HTTP request.
- A commenter objects that Bash only opens TCP sockets and does not speak HTTP.
- One commenter says the trick suits local checks but remote work should use curl.
- One commenter notes that the trick handles plain HTTP only, not HTTPS.
- A long sub-thread argues over minimal container images and whether debugging tools should be included.
- One commenter says it is a KornShell feature dating from about 1997.
- One commenter calls it an old trick used after a system has been compromised.
What evidence it gives
The evidence is the three-line example, replies from people who tried it, and many anecdotes. One reply runs it against example.com and shows the response. No benchmarks or tests are given.
Interests and limits
Most claims are commenters' recollections. The thread is about a convenience trick and does not measure reliability. The linked blog post was not read, only the thread.