fix: defer unpause in setDataStream to prevent hang on Linux#448
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The readable/end/error event handlers called unpause() synchronously, which could invoke curl_easy_pause() while libcurl was still processing the READFUNC_PAUSE return from the read callback. This reentrant call caused hangs on Linux. Defer the unpause to the next event loop tick via setImmediate, matching the pattern used by setUploadStream in Curl.ts.
setImmediate fires in the check phase of the libuv event loop, but libcurl's multi handle timeout fires in the timer phase. On Node.js 24 the setImmediate-based unpause wasn't being picked up reliably. setTimeout(fn, 0) fires in the timer phase, matching libcurl's callback scheduling and ensuring consistent behavior across Node.js versions.
The mime StaticReadCallback was returning CURL_READFUNC_PAUSE without updating pauseState, so isPausedSend/isPausedRecv both stayed false. This caused the test's conditional unpause (which checks pause state before calling curl_easy_pause) to be a silent no-op, leaving the transfer paused forever once libcurl needed a second read callback. The test only passed when the stream's 'end' event fired before libcurl's second read attempt — a race that resolved differently across Node.js versions and platforms. Additionally, the docs and examples incorrectly referenced CurlPause.Recv. The mime read callback supplies upload data, so it pauses SEND (matching Easy::ReadFunction). Updated docs, examples, and tests to use Send. Also reverted setTimeout back to setImmediate now that the underlying race is properly fixed.
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Summary
setDataStreamcalled theunpausecallback synchronously from stream event handlers (readable,end,error), which could invokecurl_easy_pause()while libcurl was still processing theREADFUNC_PAUSEreturn from the read callbackCurlMime.spec.ts > should handle basic stream upload)setImmediateand tracking pause state, matching the pattern already used bysetUploadStreaminCurl.tsTest plan
CurlMime.spec.ts > should handle basic stream uploadshould pass on Linux instead of timing out