{"record":{"id":"35850e214794ff45","repo":"golang/go","slug":"errinvalidunreadbyte","errorCode":"ErrInvalidUnreadByte","errorMessage":"bufio: invalid use of UnreadByte","messagePattern":"bufio: invalid use of UnreadByte","errorType":"error_code","errorClass":null,"httpStatus":null,"severity":"error","filePath":"src/bufio/bufio.go","lineNumber":23,"sourceCode":"// Package bufio implements buffered I/O. It wraps an io.Reader or io.Writer\n// object, creating another object (Reader or Writer) that also implements\n// the interface but provides buffering and some help for textual I/O.\npackage bufio\n\nimport (\n\t\"bytes\"\n\t\"errors\"\n\t\"io\"\n\t\"strings\"\n\t\"unicode/utf8\"\n)\n\nconst (\n\tdefaultBufSize = 4096\n)\n\nvar (\n\tErrInvalidUnreadByte = errors.New(\"bufio: invalid use of UnreadByte\")\n\tErrInvalidUnreadRune = errors.New(\"bufio: invalid use of UnreadRune\")\n\tErrBufferFull        = errors.New(\"bufio: buffer full\")\n\tErrNegativeCount     = errors.New(\"bufio: negative count\")\n)\n\n// Buffered input.\n\n// Reader implements buffering for an io.Reader object.\n// A new Reader is created by calling [NewReader] or [NewReaderSize];\n// alternatively the zero value of a Reader may be used after calling [Reader.Reset]\n// on it.\ntype Reader struct {\n\tbuf          []byte\n\trd           io.Reader // reader provided by the client\n\tr, w         int       // buf read and write positions\n\terr          error\n\tlastByte     int // last byte read for UnreadByte; -1 means invalid\n\tlastRuneSize int // size of last rune read for UnreadRune; -1 means invalid","sourceCodeStart":5,"sourceCodeEnd":41,"githubUrl":"https://github.com/golang/go/blob/b6b368adc57c96c3151d224d172029f233ead2c3/src/bufio/bufio.go#L5-L41","documentation":"Error \"bufio: invalid use of UnreadByte\" thrown in golang/go.","triggerScenarios":"Thrown at src/bufio/bufio.go:23 when the library encounters an invalid state.","commonSituations":"See trigger scenarios.","solutions":[],"exampleFix":null,"handlingStrategy":null,"validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"analyzedSha":"b6b368adc57c96c3151d224d172029f233ead2c3","analyzedAt":"2026-08-12T00:22:02.250Z","schemaVersion":2},"datasetVersion":"2026-08-12T06:17:24.410Z"}