Path Component Name Budget Checker

Audit lexical POSIX component UTF-8 byte budgets against an explicit limit; not a universal NAME_MAX or filesystem encoding claim.

Description

Audit lexical POSIX component UTF-8 byte budgets against an explicit limit; not a universal NAME_MAX or filesystem encoding claim.

Filesystem component budgets often concern encoded bytes rather than displayed character counts. This screen applies a caller-selected UTF-8 byte limit.

When to use this tool

Audit lexical POSIX component UTF-8 byte budgets against an explicit limit; not a universal NAME_MAX or filesystem encoding claim.

Prepare the supplied path, maximumUtf8Bytes fields for this operation.
Compare the complete example with the representation used by your own input before carrying the result into another step.

How to use the tool and how it works

Enter path, maximumUtf8Bytes. Use the exact text syntax, units and index conventions explained below.
Run the tool. If input validation fails, correct the supplied fields before interpreting any result.
Read result.components. Interpret false, null and empty lists using the distinctions below; they can be valid outputs.

Split the path on slash, omit empty components, reject NUL and measure each name's UTF-8 byte count. Return its index, spelling, byte count and whether it is at most maximumUtf8Bytes.^[1]

Input field	Meaning and representation	Accepted input
path	path.	Text; at most 8,192 UTF-16 code units, subject to the grammar above
maximumUtf8Bytes	maximum utf8 bytes.	Integer from 1 to 1000000 inclusive

Output field	Interpretation
result	Object containing the named outputs below.
result.components	The components list in the ordering and representation described above.

json

{
  "input": {
    "path": "a/\u00e9",
    "maximumUtf8Bytes": 1
  },
  "output": {
    "result": {
      "components": [
        {
          "index": 0,
          "name": "a",
          "utf8Bytes": 1,
          "withinBudget": true
        },
        {
          "index": 1,
          "name": "\u00e9",
          "utf8Bytes": 2,
          "withinBudget": false
        }
      ]
    }
  }
}

Limitations and assumptions

The budget is supplied rather than taken from a filesystem. No actual path is opened, and normalization, mount rules and total path length are outside the check.
Every declared top-level field is required and unexpected fields are rejected. Numeric inputs must be finite; ordinary text fields are bounded to 8,192 UTF-16 code units, with tighter operation-specific limits where stated.
String lists have at most 128 entries of at most 128 code units; matrices have at most 128 rows and columns. Larger numeric lists and parsed JSON have separate bounded budgets. Nonfinite results and excessively large serialized outputs are rejected.
Indexes are zero-based and spans have an exclusive end unless explicitly stated otherwise. A valid false, null or empty-list result is distinct from malformed input.

Alternative or Complementary methods

Use a filesystem-aware implementation with appropriate platform semantics for actual file operations. Literal slash components, Unicode comparison and filename plans do not resolve symlinks or atomically reserve a destination.

References

Tool behavior and example: Path Component Name Budget Checker — tool.io

Similar or alternative tools

Path Component Redaction Tool
Redact explicitly indexed nonempty raw slash components while preserving empty segments and terminal separators.
Relative Path Component Resolver
Lexically resolve a relative POSIX path against an absolute directory with dot collapse; no symlink or actual-file resolution.