app.ping¶

ICMP ping command that sends echo requests and reports round-trip times.

Overview¶

app.ping registers the PING shell command. Given an IPv4 address, it sends 10 ICMP echo requests with a 1-second delay between each, printing the round-trip time or an error reason for each attempt. A 5-second timeout is enforced per ping. Per-invocation state is heap-allocated so multiple terminal instances can ping concurrently without interfering with each other.

Dependencies¶

io.stdio, debug.tracer
arch.x86.bda
driver.net.types, driver.net.proto.icmp, driver.net.util
core.strings
proc.mgr
core.util, arch.x86.util
memory.heap

Constants¶

PING_TIMEOUT_MS¶

5000 — Per-ping timeout in milliseconds.

Types¶

TPingResult¶

TPingResult = (prWaiting, prGotReply, prGotError);

State of a single in-flight ping.

TPingState / PPingState¶

Per-invocation state record allocated on the heap.

Field	Type	Description
`Result`	`TPingResult`	Current result state
`ReplyTimeMS`	`uint64`	Round-trip time in timer ticks
`ErrorReason`	`TARPErrorCode`	Error code if `prGotError`
`SendTime`	`uint64`	BIOS tick counter value at send time

Functions and Procedures¶

init¶

procedure init();

Registers the PING command with io.stdio.

run (internal)¶

procedure run(Params: PParamList; stdin_buf, stdout_buf, stderr_buf: POutBuf);

Command entry point. Parses the first parameter as an IPv4 address string using stringToIPv4. Allocates a TPingState record and sends 10 ICMP requests in a loop. Between each request it spin-yields via proc.mgr.proc_yield until the reply or error callback fires, or until the timeout expires. Sleeps 1 second between pings using proc.mgr.proc_sleep_ms. Frees the state record and IP buffer on completion.

on_reply (internal)¶

ICMP callback: records the elapsed time and sets Result to prGotReply.

on_error (internal)¶

ICMP callback: records the error reason and sets Result to prGotError.

Notes¶

Round-trip time is reported in BIOS timer ticks (the counter runs at approximately 1024 Hz), not milliseconds. Error reasons include: aecFailedToResolveHost, aecNoRouteToHost, aecTimeout, and aecTTLExpired.