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Diffstat (limited to 'gnulib/doc/posix-functions/unlinkat.texi')
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diff --git a/gnulib b/gnulib deleted file mode 160000 -Subproject 443bc5ffcf7429e557f4a371b0661abe98ddbc1 diff --git a/gnulib/doc/posix-functions/unlinkat.texi b/gnulib/doc/posix-functions/unlinkat.texi new file mode 100644 index 0000000..6bb9436 --- /dev/null +++ b/gnulib/doc/posix-functions/unlinkat.texi @@ -0,0 +1,51 @@ +@node unlinkat +@section @code{unlinkat} +@findex unlinkat + +POSIX specification:@* @url{http://www.opengroup.org/onlinepubs/9699919799/functions/unlinkat.html} + +Gnulib module: unlinkat + +Portability problems fixed by Gnulib: +@itemize +@item +This function is missing on some platforms: +glibc 2.3.6, MacOS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, +AIX 5.1, HP-UX 11, IRIX 6.5, OSF/1 5.1, Cygwin 1.5.x, mingw, MSVC 9, Interix 3.5, BeOS. +But the replacement function is not safe to be used in libraries and is not multithread-safe. +@item +Some systems mistakenly succeed on @code{unlinkat(fd,"file/",flag)}: +GNU/Hurd, Solaris 9. +@item +Some platforms declare this function in @code{fcntl.h} instead of +@code{unistd.h}: +Cygwin 1.7.1. +@end itemize + +Portability problems not fixed by Gnulib: +@itemize +@item +When @code{unlinkat(fd,name,AT_REMOVEDIR)} fails because the specified +directory is not empty, the @code{errno} value is system dependent. +@item +POSIX requires that @code{unlinkdir(fd,"link-to-empty/",AT_REMOVEDIR)} +remove @file{empty} and leave @file{link-to-empty} as a dangling +symlink. This is counter-intuitive, so some systems fail with +@code{ENOTDIR} instead: +glibc +@item +Some systems allow a superuser to unlink directories, even though this +can cause file system corruption. The error given if a process is not +permitted to unlink directories varies across implementations; it is +not always the POSIX value of @code{EPERM}. Meanwhile, if a process +has the ability to unlink directories, POSIX requires that +@code{unlinkat(fd,"symlink-to-dir/",0)} remove @file{dir} and leave +@file{symlink-to-dir} dangling; this behavior is counter-intuitive. +The gnulib module unlinkdir can help determine whether code must be +cautious of unlinking directories. +@item +Removing an open file is non-portable: On Unix this allows the programs that +have the file already open to continue working with it; the file's storage +is only freed when the no process has the file open any more. On Windows, +the attempt to remove an open file fails. +@end itemize |