<html>
<head>
<base href="https://bugs.llvm.org/">
</head>
<body><table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - std::ofstream silently fails to write files when they can't be created"
href="https://bugs.llvm.org/show_bug.cgi?id=42572">42572</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>std::ofstream silently fails to write files when they can't be created
</td>
</tr>
<tr>
<th>Product</th>
<td>libc++
</td>
</tr>
<tr>
<th>Version</th>
<td>unspecified
</td>
</tr>
<tr>
<th>Hardware</th>
<td>PC
</td>
</tr>
<tr>
<th>OS</th>
<td>FreeBSD
</td>
</tr>
<tr>
<th>Status</th>
<td>NEW
</td>
</tr>
<tr>
<th>Severity</th>
<td>enhancement
</td>
</tr>
<tr>
<th>Priority</th>
<td>P
</td>
</tr>
<tr>
<th>Component</th>
<td>All Bugs
</td>
</tr>
<tr>
<th>Assignee</th>
<td>unassignedclangbugs@nondot.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>yuri@tsoft.com
</td>
</tr>
<tr>
<th>CC</th>
<td>llvm-bugs@lists.llvm.org, mclow.lists@gmail.com
</td>
</tr></table>
<p>
<div>
<pre>The example from cplusplus.com
<a href="http://www.cplusplus.com/reference/fstream/ofstream/open/">http://www.cplusplus.com/reference/fstream/ofstream/open/</a> with the modified
file name fails silently, showing how error-prone the file interface is:
<span class="quote">> #include <fstream>
>
> int main () {
> std::ofstream ofs;
> ofs.open ("nonexistent-noexistent/test.txt", std::ofstream::out | std::ofstream::app);
>
> ofs << " more lorem ipsum";
>
> ofs.close();
>
> return 0;
> }</span >
No exception is thrown, no error message is printed.
The kernel trace shows that the error "No such file or directory" is lost by
STL:
<span class="quote">> 47377 ofstream CALL open(0x20229d,0x209<O_WRONLY|O_APPEND|O_CREAT>,0666<S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH>)
> 47377 ofstream NAMI "nonexistent-noexistent/test.txt"
> 47377 ofstream RET open -1 errno 2 No such file or directory</span >
FreeBSD 12 amd64, clang8.
Yuri</pre>
</div>
</p>
<hr>
<span>You are receiving this mail because:</span>
<ul>
<li>You are on the CC list for the bug.</li>
</ul>
</body>
</html>