{"record":{"id":"071d207f3158decd","repo":"caddyserver/caddy","slug":"determining-current-executable-path-v","errorCode":null,"errorMessage":"determining current executable path: %v","messagePattern":"determining current executable path: (.+?)","errorType":"console","errorClass":null,"httpStatus":null,"severity":"error","filePath":"cmd/packagesfuncs.go","lineNumber":129,"sourceCode":"\t\tif err != nil {\n\t\t\treturn caddy.ExitCodeFailedStartup, fmt.Errorf(\"invalid module name: %v\", err)\n\t\t}\n\t\tif _, ok := pluginPkgs[module]; !ok {\n\t\t\t// package does not exist\n\t\t\treturn caddy.ExitCodeFailedStartup, fmt.Errorf(\"package is not added\")\n\t\t}\n\t\tdelete(pluginPkgs, arg)\n\t}\n\n\treturn upgradeBuild(pluginPkgs, fl)\n}\n\nfunc upgradeBuild(pluginPkgs map[string]pluginPackage, fl Flags) (int, error) {\n\tl := caddy.Log()\n\n\tthisExecPath, err := os.Executable()\n\tif err != nil {\n\t\treturn caddy.ExitCodeFailedStartup, fmt.Errorf(\"determining current executable path: %v\", err)\n\t}\n\tthisExecStat, err := os.Stat(thisExecPath)\n\tif err != nil {\n\t\treturn caddy.ExitCodeFailedStartup, fmt.Errorf(\"retrieving current executable permission bits: %v\", err)\n\t}\n\tif thisExecStat.Mode()&os.ModeSymlink == os.ModeSymlink {\n\t\tsymSource := thisExecPath\n\t\t// we are a symlink; resolve it\n\t\tthisExecPath, err = filepath.EvalSymlinks(thisExecPath)\n\t\tif err != nil {\n\t\t\treturn caddy.ExitCodeFailedStartup, fmt.Errorf(\"resolving current executable symlink: %v\", err)\n\t\t}\n\t\tl.Info(\"this executable is a symlink\", zap.String(\"source\", symSource), zap.String(\"target\", thisExecPath))\n\t}\n\tl.Info(\"this executable will be replaced\", zap.String(\"path\", thisExecPath))\n\n\t// build the request URL to download this custom build\n\tqs := url.Values{","sourceCodeStart":111,"sourceCodeEnd":147,"githubUrl":"https://github.com/caddyserver/caddy/blob/50e54ee279aa1e504fe218ca49ab6ae16c100410/cmd/packagesfuncs.go#L111-L147","documentation":"upgradeBuild cannot determine the path of the running Caddy executable (os.Executable failed) before replacing it with a freshly downloaded build. Without the current path, the upgrade cannot back up or overwrite the binary, so it aborts with ExitCodeFailedStartup.","triggerScenarios":"The running binary was deleted or replaced while the process is alive (common when a prior upgrade attempt half-completed), or /proc is not mounted (os.Executable reads /proc/self/exe on Linux) — e.g. inside minimal containers or gVisor sandboxes.","commonSituations":"Running `caddy upgrade` in a container without /proc; a package manager replaced the file at the same path; running from a deleted temp directory.","solutions":["Check /proc is mounted and readable (`ls -l /proc/self/exe`) in the environment running the command","If the binary file was deleted/renamed, restore it (reinstall) so os.Executable resolves again, then retry","Prefer upgrading via xcaddy or downloading a new binary to a fresh path rather than in-place upgrade in constrained environments"],"exampleFix":null,"handlingStrategy":"validation","validationCode":"# verify the running executable can be resolved before upgrading\nls -l /proc/self/exe >/dev/null 2>&1 || echo '/proc unavailable; in-place upgrade will fail'\nreadlink -f \"$(command -v caddy)\" >/dev/null || echo 'caddy path unresolvable'","typeGuard":null,"tryCatchPattern":null,"preventionTips":["Run in-place upgrades only where /proc is mounted (bare metal, normal containers)","Keep binaries at stable paths that are not deleted while running"],"tags":["caddy","upgrade","os","executable","containers"],"backgroundTag":null,"analyzedSha":"50e54ee279aa1e504fe218ca49ab6ae16c100410","analyzedAt":"2026-08-15T09:20:21.641Z","schemaVersion":2},"datasetVersion":"2026-08-15T17:31:12.345Z"}