💻 Developer#Hex#디버깅#로그분석
Reading Hex Logs: A Practical Debugging Guide
5 min read · Last updated: 2026-05-08
What is a Hex log (hex dump)?
A hex dump displays raw binary data as two-digit hexadecimal values (00–FF) for each byte, often accompanied by a printable ASCII column on the right. It is the fundamental tool for inspecting serial communications, network packets, and binary file contents.
Reading a hex dump
Offset Hex data ASCII
00000000: 48 65 6C 6C 6F 2C 20 57 6F 72 6C 64 21 0A Hello, World!.- Offset: Byte position in the file or stream (in hex)
- Hex data: Each byte as two hex digits
- ASCII column: Non-printable bytes shown as
.
Common patterns and their meanings
| Pattern | Meaning |
|---|---|
FF FE / FE FF | UTF-16 BOM (byte order mark) |
EF BB BF | UTF-8 BOM |
00 00 00 00 | NULL / zero-initialized region |
DE AD BE EF | Debug magic number (uninitialized memory marker) |
0D 0A | Windows line ending (CRLF) |
0A | Unix/Linux line ending (LF) |
7F 45 4C 46 (ELF) | Linux executable signature |
4D 5A (MZ) | Windows executable signature |
Reading error codes
Error code 0xC0000005 is the Windows Access Violation status. Hex error codes can be looked up directly in OS or library documentation to find their meaning.
Accessing address 0x00000000 → likely a null pointer dereference.
Key takeaways
- Hex dumps let you inspect data at the byte level — the most fundamental debugging technique.
- File signatures (magic bytes) identify file formats regardless of extension.
- BOMs, line endings, and null bytes are the first things to check when diagnosing encoding issues.
- Search error codes as hex values in official documentation for quick identification.