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RemoveReadOnly

Function RemoveReadOnly( const FileName : string) : Boolean

Example​

procedure ScriptEvent(var Value: variant);
begin
  // Attribute-changing operation; use only on a governed path.
  Value := RemoveReadOnly('C:\Fictional\Inbound\order.xml');
end;

Usage​

RemoveReadOnly returns success when a path is not read-only, or replaces all attributes with normal and verifies the result.

Parameters

NameTypeDescription
FileNamestring, constPath passed both to wildcard-capable FileIsReadOnly and, when needed, literally to SetFileAttributesW.

Returns

True when the first query returns false, or when the verification query returns false after the API call; False only when read-only is seen both before and after.

Behaviour

  • A file already reported writable returns True without calling Windows.
  • A read-only file is reset to normal and queried again.
  • The Boolean result of SetFileAttributesW and its last-error detail are discarded.
  • No content is opened or changed.

Errors

Ordinary query and attribute-setting errors are not raised or exposed. Unexpected runtime failures can propagate.

Usage notes

Use a literal verified path. If preserving hidden/archive/system or other flags matters, this helper is unsuitable; use an operation that reads the current bit set and clears only read-only with checked error handling.

Additional Technical Info​

RemoveReadOnly returns True immediately when FileIsReadOnly returns false. If that query finds a read-only entry, Velox calls Windows SetFileAttributesW(FileName, FILE_ATTRIBUTE_NORMAL), ignores the API return value, and reports whether a second query no longer sees read-only.

The example is fictional, source-reviewed and was not executed by the documentation workflow. A real call changes file-system attributes.

Implementation

The function does not read and preserve the existing attribute bit set. FILE_ATTRIBUTE_NORMAL is value $80 and is valid only by itself, so a successful call replaces supported attributes with “normal” rather than clearing only FILE_ATTRIBUTE_READONLY.

Edge cases and quirks

  • A missing, inaccessible or search-error path normally returns True, because FileIsReadOnly collapses those states to false.
  • A successful reset can also remove hidden, system, archive, temporary or other attributes that Windows permits this API to change.
  • Wildcards are unsafe here: the first query can match an entry, while SetFileAttributesW receives the literal wildcard text and normally fails; a later first match can also differ.
  • Directory entries can match the initial search. Reset support and consequences then follow Windows directory-attribute rules.
  • The verification is another racy snapshot and does not prove later write permission or successful content access.

Side effects

Can replace the target's supported Windows attribute set with FILE_ATTRIBUTE_NORMAL.

Performance and concurrency

One search when no read-only match is seen; otherwise two searches plus an attribute update. Remote storage can block, and concurrent attribute/path changes can invalidate the conclusion.

Related entries

  • FileIsReadOnly defines the wildcard and false-on-query-error behavior inherited here.
  • vxDeleteFile requires read-only to be removed before Windows can delete a read-only file.
  • FileLocked tests one access/share mode, not attributes.

External references

No applicable same-symbol Embarcadero core routine is called by this Velox wrapper.

Created 2026-07-15