D 2026-07-19T16:49:57.465
T +comment d7dd9ea30b699786231766b23c5f03cbd318a764f35ced28641128c4d94b00b3 mv:\smove\sthe\sworking\sfile\sbefore\srecording;\sfailed\smv\srecords\snothing\n\nmv\srecorded\sthe\srename\sdurably\sbefore\sattempting\sthe\sfilesystem\smove\sand\nrolled\snothing\sback\swhen\sit\sfailed,\sleaving\sthe\sset\snaming\sa\spath\sthat\sdoes\nnot\sexist\sand\scommit\sready\sto\srecord\sa\srename\sthat\snever\shappened.\sThe\nreversal\smv\s--help\spromises\s--\s"run\szit\smv\sNEW\sOLD"\s--\sfailed\stoo:\sit\ssaw\sthe\nold\spath\sstill\soccupied\sand\srefused\sthe\scollision.\n\nmvCommit\snow\srenames\sfirst,\sthen\srecords;\sif\sthe\srecord\sfails\sthe\sfile\sis\nrenamed\sback\sand\snothing\sis\spersisted.\sMove-first\sbeats\srecord-first\sbecause\nundoing\sa\sdurable\swrite\sneeds\sa\ssecond\sdurable\swrite,\swhich\scan\sitself\sfail,\nnesting\sa\sfailure\sinside\sthe\sfailure\shandler.\sRenaming\sa\sfile\sback\scannot\nrealistically\sfail\s--\sthe\ssource\sdirectory\sand\sname\sare\sstill\sfree.\sBuild\sthe\nguarantee\son\sthe\srollback\sthat\scannot\sfail.\n\nmvCheckLegal\sgains\sa\sdest-parent-exists\scheck:\sstat\sof\sa\spath\sunder\sa\smissing\ndirectory\sfails,\sso\sthe\sold\scollision\scheck\sread\s"absent"\sand\swaved\sit\sthrough.\nResidual\swindow:\sa\scrash\sbetween\smove\sand\srecord\sleaves\sthe\sfile\sat\sNEW\swith\nthe\sset\snaming\sOLD,\srecoverable\swith\sadd\sNEW\s+\srm\sOLD.\n\nENOENT\sand\sEACCES\swere\sboth\srendered\s"input/output\serror".\n
U dmestas
Z 1c245f9b0cbd4e3b0df03539ee7cf92d