Bug 55821 - DllImport not compatible with CLR
Summary: DllImport not compatible with CLR
Status: NEW
Alias: None
Product: Runtime
Classification: Mono
Component: Interop ()
Version: unspecified
Hardware: PC Windows
: --- normal
Target Milestone: ---
Assignee: Bugzilla
Depends on:
Reported: 2017-04-29 22:50 UTC by Marius Ungureanu
Modified: 2017-04-29 23:01 UTC (History)
2 users (show)

Is this bug a regression?: ---
Last known good build:

Notice (2018-05-24): bugzilla.xamarin.com is now in read-only mode.

Please join us on Visual Studio Developer Community and in the Xamarin and Mono organizations on GitHub to continue tracking issues. Bugzilla will remain available for reference in read-only mode. We will continue to work on open Bugzilla bugs, copy them to the new locations as needed for follow-up, and add the new items under Related Links.

Our sincere thanks to everyone who has contributed on this bug tracker over the years. Thanks also for your understanding as we make these adjustments and improvements for the future.

Please create a new report for Bug 55821 on GitHub or Developer Community if you have new information to add and do not yet see a matching new report.

If the latest results still closely match this report, you can use the original description:

  • Export the original title and description: GitHub Markdown or Developer Community HTML
  • Copy the title and description into the new report. Adjust them to be up-to-date if needed.
  • Add your new information.

In special cases on GitHub you might also want the comments: GitHub Markdown with public comments

Related Links:

Description Marius Ungureanu 2017-04-29 22:50:26 UTC
Given an extern definition for printf:

static extern int printf(string format, int num);

on Windows, the following DllImport's are valid

[DllImport("msvcrt.dll    ")]
[DllImport("msvcrt.dll                        ")]

This is not valid though:

[DllImport(" msvcrt.dll")]

On Mono, this fails with dll not found. Probably, Windows does a TrimEnd on the library name.
Comment 1 Marius Ungureanu 2017-04-29 23:01:46 UTC
var attr = typeof(MainClass).GetMethod("printf", BindingFlags.Static | BindingFlags.NonPublic).GetCustomAttribute<DllImportAttribute>();

attr.Value includes the whitespace.

So the fix is in the library loading code.

This is the only member that supports trailing whitespace removal.