Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752229AbaAPKxY (ORCPT ); Thu, 16 Jan 2014 05:53:24 -0500 Received: from mail-wi0-f175.google.com ([209.85.212.175]:46077 "EHLO mail-wi0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751552AbaAPKxW (ORCPT ); Thu, 16 Jan 2014 05:53:22 -0500 Date: Thu, 16 Jan 2014 11:54:06 +0100 From: Miklos Szeredi To: Michael Kerrisk Cc: "J. Bruce Fields" , Jan Kara , Al Viro , Linus Torvalds , Linux-Fsdevel , Kernel Mailing List , Christoph Hellwig , Andrew Morton , David Howells , Zach Brown , Andy Lutomirski , "mszeredi@suse.cz" Subject: Re: [PATCH 11/11] ext4: add cross rename support Message-ID: <20140116105406.GF24171@tucsk.piliscsaba.szeredi.hu> References: <1389219015-10980-1-git-send-email-miklos@szeredi.hu> <1389219015-10980-12-git-send-email-miklos@szeredi.hu> <20140113122517.GA10366@quack.suse.cz> <20140115182347.GB5715@fieldses.org> MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="cNdxnHkX5QqsyA0e" Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --cNdxnHkX5QqsyA0e Content-Type: text/plain; charset=us-ascii Content-Disposition: inline > On Wed, Jan 15, 2014 at 7:23 PM, J. Bruce Fields wrote: > > Do you have a man page update somewhere for the two new flags? Here's the updated man page (and attached the patch) Michael, could you please review the interface? I forgot to CC you when posing the patch series. I can resend it if you want, or you can fetch the latest version of the cross-rename series from: git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs.git cross-rename Thanks, Miklos ---- RENAMEAT(2) Linux Programmer's Manual RENAMEAT(2) NAME renameat, renameat2 - rename a file relative to directory file descrip- tors SYNOPSIS #include /* Definition of AT_* constants */ #include int renameat(int olddirfd, const char *oldpath, int newdirfd, const char *newpath); int renameat2(int olddirfd, const char *oldpath, int newdirfd, const char *newpath, unsigned int flags); Feature Test Macro Requirements for glibc (see feature_test_macros(7)): renameat(): Since glibc 2.10: _XOPEN_SOURCE >= 700 || _POSIX_C_SOURCE >= 200809L Before glibc 2.10: _ATFILE_SOURCE DESCRIPTION The renameat() and renameat2() system calls operate in exactly the same way as rename(2), except for the differences described in this manual page. If the pathname given in oldpath is relative, then it is interpreted relative to the directory referred to by the file descriptor olddirfd (rather than relative to the current working directory of the calling process, as is done by rename(2) for a relative pathname). If oldpath is relative and olddirfd is the special value AT_FDCWD, then oldpath is interpreted relative to the current working directory of the calling process (like rename(2)). If oldpath is absolute, then olddirfd is ignored. The interpretation of newpath is as for oldpath, except that a relative pathname is interpreted relative to the directory referred to by the file descriptor newdirfd. renameat2() has an additional flags argument. renameat2() call with a zero flags argument is equivalent to renameat(). The flags argument is a bitfield consisting of zero or more of the fol- lowing constants defined in : RENAME_NOREPLACE Don't overwrite the target of the rename. Return an error if the target would be overwritten. RENAME_EXCHANGE Atomically exchange the source and destination. Both must exist but may be of a different type (e.g. one a non-empty directory and the other a symbolic link). RETURN VALUE On success, renameat() and renameat2() return 0. On error, -1 is returned and errno is set to indicate the error. ERRORS The same errors that occur for rename(2) can also occur for renameat() and renameat2(). The following additional errors can occur for renameat() and renameat2(): EBADF olddirfd or newdirfd is not a valid file descriptor. ENOTDIR oldpath is relative and olddirfd is a file descriptor referring to a file other than a directory; or similar for newpath and newdirfd The following additional errors are defined for renameat2(): EOPNOTSUPP The filesystem does not support a flag in flags EINVAL Invalid combination of flags EEXIST flags contain RENAME_NOREPLACE and the target of the rename exists ENOENT flags contain RENAME_EXCHANGE and the target of the rename does not exist VERSIONS renameat() was added to Linux in kernel 2.6.16; library support was added to glibc in version 2.4. CONFORMING TO renameat() is specified in POSIX.1-2008. NOTES See openat(2) for an explanation of the need for renameat(). SEE ALSO openat(2), rename(2), path_resolution(7) Linux 2012-05-04 RENAMEAT(2) --cNdxnHkX5QqsyA0e Content-Type: text/x-patch; charset=us-ascii Content-Disposition: attachment; filename="renameat.2.patch" diff --git a/man2/renameat.2 b/man2/renameat.2 index 432ddfd..e2f80d8 100644 --- a/man2/renameat.2 +++ b/man2/renameat.2 @@ -24,7 +24,7 @@ .\" .TH RENAMEAT 2 2012-05-04 "Linux" "Linux Programmer's Manual" .SH NAME -renameat \- rename a file relative to directory file descriptors +renameat, renameat2 \- rename a file relative to directory file descriptors .SH SYNOPSIS .nf .B #include /* Definition of AT_* constants */ @@ -32,6 +32,9 @@ renameat \- rename a file relative to directory file descriptors .sp .BI "int renameat(int " olddirfd ", const char *" oldpath , .BI " int " newdirfd ", const char *" newpath ); + +.BI "int renameat2(int " olddirfd ", const char *" oldpath , +.BI " int " newdirfd ", const char *" newpath ", unsigned int " flags ); .fi .sp .in -4n @@ -55,7 +58,9 @@ _ATFILE_SOURCE .SH DESCRIPTION The .BR renameat () -system call operates in exactly the same way as +and +.BR renameat2 () +system calls operate in exactly the same way as .BR rename (2), except for the differences described in this manual page. @@ -94,10 +99,37 @@ is as for except that a relative pathname is interpreted relative to the directory referred to by the file descriptor .IR newdirfd . + +.BR renameat2 () +has an additional +.I flags +argument. +.BR renameat2 () +call with a zero +.I flags +argument is equivalent to +.BR renameat (). + +The +.I flags +argument is a bitfield consisting of zero or more of the following +constants defined in +.IR : +.TP +.B RENAME_NOREPLACE +Don't overwrite the target of the rename. Return an error +if the target would be overwritten. +.TP +.B RENAME_EXCHANGE +Atomically exchange the source and destination. Both must exist +but may be of a different type (e.g. one a non-empty directory +and the other a symbolic link). .SH RETURN VALUE On success, .BR renameat () -returns 0. +and +.BR renameat2 () +return 0. On error, \-1 is returned and .I errno is set to indicate the error. @@ -105,9 +137,13 @@ is set to indicate the error. The same errors that occur for .BR rename (2) can also occur for -.BR renameat (). +.BR renameat () +and +.BR renameat2 (). The following additional errors can occur for -.BR renameat (): +.BR renameat () +and +.BR renameat2 (): .TP .B EBADF .I olddirfd @@ -124,12 +160,37 @@ or similar for .I newpath and .I newdirfd +.RE +.PP +The following additional errors are defined for +.BR renameat2 (): +.TP +.B EOPNOTSUPP +The filesystem does not support a flag in +.I flags +.TP +.B EINVAL +Invalid combination of +.I flags +.TP +.B EEXIST +.I flags +contain +.B RENAME_NOREPLACE +and the target of the rename exists +.TP +.B ENOENT +.I flags +contain +.B RENAME_EXCHANGE +and the target of the rename does not exist .SH VERSIONS .BR renameat () was added to Linux in kernel 2.6.16; library support was added to glibc in version 2.4. .SH CONFORMING TO -POSIX.1-2008. +.BR renameat () +is specified in POSIX.1-2008. .SH NOTES See .BR openat (2) --cNdxnHkX5QqsyA0e-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/