Execution walks.

slos:/$ note add map the write path before changing it
Note #7 added.
slos:/$ note tag last manual
Tagged note #7 with manual
slos:/$ tl show notes
#2386 notes NOTE_ADD map the write path before changing it
#2387 notes NOTE_TAG manual
slos:/$ why 2387
[2387] notes: tag note #7 manual
  caused by [2386] notes: map the write path before changing it

slos:/$ diskmkdir /docs
slos:/$ diskwrite /docs/boot.html "<h1>Boot notes</h1><p>Rendered by browser.</p>"
slos:/$ exec browser file:/docs/boot.html -find browser
[elf] loaded 'browser' (entry 0x40000000, pid 42)
SlOS Browser ELF: file:/docs/boot.html (32 bytes)
Matches:
  Rendered by browser.
Ran 'browser' (pid 42)
slos:/$ events 5
  ID    TICK    TYPE        DESCRIPTION
  2410  12004   elf         exec: browser at 0x40000000
  2411  12005   syscall     syscall 73 pid=42
  2412  12006   syscall     syscall 48 pid=42
  2413  12007   syscall     syscall 1 pid=42
  2414  12008   syscall     syscall 0 pid=42

slos:/$ httpd
[httpd] Listening on port 80 — dashboard at http://<ip>/
host$ curl http://localhost:8080/api/sysinfo
{"version":"SlOS 0.1.0","uptime_ticks":22690,"total_events":2519}
slos:/$ tcptrace
Recent TCP causal events:
  [2516] T+22690  conn 1: CLOSED → SYN_RCVD (port 80)
  [2517] T+22691  conn 1: SYN_RCVD → ESTABLISHED (port 80)  [←2516]
  [2518] T+22692  conn 1: send 42 bytes  [←2517]
  [2519] T+22693  conn 1: ESTABLISHED → CLOSE_WAIT (port 80)  [←2518]

slos:/$ diskmkdir /log
slos:/$ diskwrite /log/run.txt sector path recorded
slos:/$ diskstat /log/run.txt
/log/run.txt: inode=7 type=file size=21 bytes blocks=1 ctime=T+123 mtime=T+123 flags=rw
slos:/$ diskcat /log/run.txt
sector path recorded
slos:/$ fsck
fsck: clean

slos:/$ actors
  ID  NAME                 PID  MSGS  IN/OUT
  2   shell                0    0     3/0
slos:/$ send shell local loop
Sent to shell: local loop
slos:/$ recv shell
[type=1 from=2 t=30211] local loop
slos:/$ trace 2732
2732 actor recv name=shell type=1
  caused by 2731 actor send to=shell

slos:/$ doom
[elf] loaded 'doom' (entry 0x40000000, pid 52)
<screen enters 320x200 256-colour graphics mode>
<doomgeneric reads /doom2.wad and draws frames>
slos:/$ events 6
2810 elf exec: doom at 0x40000000
2811 syscall FB_INIT pid=52
2812 syscall FB_PALETTE pid=52
2813 syscall FB_BLIT pid=52
2814 syscall POLL_KEY pid=52
2815 syscall SLEEP pid=52

slos:/$ journal spill-through last
journal spill-through: event #3912 archived (spilled 1)
slos:/$ events 10
#3912 is no longer in the hot ring
slos:/$ why 3912
(event 3912 beyond recent history)
slos:/$ why -a 3912
Journal trace for event #3912:
  #3912  T+39012 hash=0xabc123 hashv=4 source=journal transport=syscall hash_cmd="journal hash 3912" shell  shell    command complete
  caused by:
    #3911  T+39011 hash=0xdef456 hashv=4 source=journal transport=syscall hash_cmd="journal hash 3911" syscall syscall  syscall 1 pid=37
slos:/$ trace -a 3912
Journal trace for event #3912:
  #3912  T+39012 hash=0xabc123 hashv=4 source=journal transport=syscall hash_cmd="journal hash 3912" shell  shell    command complete

slos:/$ httpd
[httpd] Listening on port 80 — dashboard at http://<ip>/
host$ xdg-open http://localhost:8080/causal
browser: GET /causal
browser: GET /api/causal/graph
browser: render SVG nodes and parent edges
browser: click #4120 to focus causes and effects
browser: GET /api/causal/state?tick=100

slos:/$ scrub 100
SlOS Causal Time-Travel  tick 100 / 999
[====------------------------------------]
Reconstructed state (replay of 100 events):
  tasks: alive 3  created 4  exited 1
  io:    syscalls 18  fs 2  net tx/rx 0/0  actor msgs 1
Active tasks (3):
  [pid 1] shell
Recent events (4): #97 #98 #99 #100
slos:/$ scrub diff 100 999
Causal diff: tick 100 -> tick 999
  events +899   syscalls +12   fs +3
  net tx +0   net rx +0   actor +12
  tasks alive: 3 -> 7
slos:/$ scrub json 100
{"tick":100,"total_events":100,"tasks":{"alive":3,"created":4,"exited":1},"io":{"syscalls":18,"fs":2,"net_tx":0,"net_rx":0,"actor_msgs":1},"active_tasks":[{"pid":1,"name":"shell"}],"recent_events":[97,98,99,100]}

slos:/$ lens save syscall cq -a type=syscall limit=10
lens: saved 'syscall' = cq -a type=syscall limit=10
slos:/$ lens list
Saved causal lenses
  syscall      cq -a type=syscall limit=10
slos:/$ reboot
...
slos:/$ lens run syscall
CQ results (archived journal):
slos:/$ diskcat /lens.db
syscall cq -a type=syscall limit=10