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diff --git a/man2/link.2 b/man2/link.2 deleted file mode 100644 index 74437a0..0000000 --- a/man2/link.2 +++ /dev/null @@ -1,425 +0,0 @@ -.\" This manpage is Copyright (C) 1992 Drew Eckhardt; -.\" and Copyright (C) 1993 Michael Haardt, Ian Jackson. -.\" and Copyright (C) 2006, 2014 Michael Kerrisk -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.\" Modified 1993-07-23 by Rik Faith <faith@cs.unc.edu> -.\" Modified 1994-08-21 by Michael Haardt -.\" Modified 2004-06-23 by Michael Kerrisk <mtk.manpages@gmail.com> -.\" Modified 2005-04-04, as per suggestion by Michael Hardt for rename.2 -.\" -.TH link 2 2023-10-31 "Linux man-pages 6.7" -.SH NAME -link, linkat \- make a new name for a file -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.B #include <unistd.h> -.P -.BI "int link(const char *" oldpath ", const char *" newpath ); -.P -.BR "#include <fcntl.h> " "/* Definition of " AT_* " constants */" -.B #include <unistd.h> -.P -.BI "int linkat(int " olddirfd ", const char *" oldpath , -.BI " int " newdirfd ", const char *" newpath ", int " flags ); -.fi -.P -.RS -4 -Feature Test Macro Requirements for glibc (see -.BR feature_test_macros (7)): -.RE -.P -.BR linkat (): -.nf - Since glibc 2.10: - _POSIX_C_SOURCE >= 200809L - Before glibc 2.10: - _ATFILE_SOURCE -.fi -.SH DESCRIPTION -.BR link () -creates a new link (also known as a hard link) to an existing file. -.P -If -.I newpath -exists, it will -.I not -be overwritten. -.P -This new name may be used exactly as the old one for any operation; -both names refer to the same file (and so have the same permissions -and ownership) and it is impossible to tell which name was the -"original". -.SS linkat() -The -.BR linkat () -system call operates in exactly the same way as -.BR link (), -except for the differences described here. -.P -If the pathname given in -.I oldpath -is relative, then it is interpreted relative to the directory -referred to by the file descriptor -.I olddirfd -(rather than relative to the current working directory of -the calling process, as is done by -.BR link () -for a relative pathname). -.P -If -.I oldpath -is relative and -.I olddirfd -is the special value -.BR AT_FDCWD , -then -.I oldpath -is interpreted relative to the current working -directory of the calling process (like -.BR link ()). -.P -If -.I oldpath -is absolute, then -.I olddirfd -is ignored. -.P -The interpretation of -.I newpath -is as for -.IR oldpath , -except that a relative pathname is interpreted relative -to the directory referred to by the file descriptor -.IR newdirfd . -.P -The following values can be bitwise ORed in -.IR flags : -.TP -.BR AT_EMPTY_PATH " (since Linux 2.6.39)" -.\" commit 11a7b371b64ef39fc5fb1b6f2218eef7c4d035e3 -If -.I oldpath -is an empty string, create a link to the file referenced by -.I olddirfd -(which may have been obtained using the -.BR open (2) -.B O_PATH -flag). -In this case, -.I olddirfd -can refer to any type of file except a directory. -This will generally not work if the file has a link count of zero (files -created with -.B O_TMPFILE -and without -.B O_EXCL -are an exception). -The caller must have the -.B CAP_DAC_READ_SEARCH -capability in order to use this flag. -This flag is Linux-specific; define -.B _GNU_SOURCE -.\" Before glibc 2.16, defining _ATFILE_SOURCE sufficed -to obtain its definition. -.TP -.BR AT_SYMLINK_FOLLOW " (since Linux 2.6.18)" -By default, -.BR linkat (), -does not dereference -.I oldpath -if it is a symbolic link (like -.BR link ()). -The flag -.B AT_SYMLINK_FOLLOW -can be specified in -.I flags -to cause -.I oldpath -to be dereferenced if it is a symbolic link. -If procfs is mounted, -this can be used as an alternative to -.BR AT_EMPTY_PATH , -like this: -.IP -.in +4n -.EX -linkat(AT_FDCWD, "/proc/self/fd/<fd>", newdirfd, - newname, AT_SYMLINK_FOLLOW); -.EE -.in -.P -Before Linux 2.6.18, the -.I flags -argument was unused, and had to be specified as 0. -.P -See -.BR openat (2) -for an explanation of the need for -.BR linkat (). -.SH RETURN VALUE -On success, zero is returned. -On error, \-1 is returned, and -.I errno -is set to indicate the error. -.SH ERRORS -.TP -.B EACCES -Write access to the directory containing -.I newpath -is denied, or search permission is denied for one of the directories -in the path prefix of -.I oldpath -or -.IR newpath . -(See also -.BR path_resolution (7).) -.TP -.B EDQUOT -The user's quota of disk blocks on the filesystem has been exhausted. -.TP -.B EEXIST -.I newpath -already exists. -.TP -.B EFAULT -.IR oldpath " or " newpath " points outside your accessible address space." -.TP -.B EIO -An I/O error occurred. -.TP -.B ELOOP -Too many symbolic links were encountered in resolving -.IR oldpath " or " newpath . -.TP -.B EMLINK -The file referred to by -.I oldpath -already has the maximum number of links to it. -For example, on an -.BR ext4 (5) -filesystem that does not employ the -.I dir_index -feature, the limit on the number of hard links to a file is 65,000; on -.BR btrfs (5), -the limit is 65,535 links. -.TP -.B ENAMETOOLONG -.IR oldpath " or " newpath " was too long." -.TP -.B ENOENT -A directory component in -.IR oldpath " or " newpath -does not exist or is a dangling symbolic link. -.TP -.B ENOMEM -Insufficient kernel memory was available. -.TP -.B ENOSPC -The device containing the file has no room for the new directory -entry. -.TP -.B ENOTDIR -A component used as a directory in -.IR oldpath " or " newpath -is not, in fact, a directory. -.TP -.B EPERM -.I oldpath -is a directory. -.TP -.B EPERM -The filesystem containing -.IR oldpath " and " newpath -does not support the creation of hard links. -.TP -.BR EPERM " (since Linux 3.6)" -The caller does not have permission to create a hard link to this file -(see the description of -.I /proc/sys/fs/protected_hardlinks -in -.BR proc (5)). -.TP -.B EPERM -.I oldpath -is marked immutable or append-only. -(See -.BR ioctl_iflags (2).) -.TP -.B EROFS -The file is on a read-only filesystem. -.TP -.B EXDEV -.IR oldpath " and " newpath -are not on the same mounted filesystem. -(Linux permits a filesystem to be mounted at multiple points, but -.BR link () -does not work across different mounts, -even if the same filesystem is mounted on both.) -.P -The following additional errors can occur for -.BR linkat (): -.TP -.B EBADF -.I oldpath -.RI ( newpath ) -is relative but -.I olddirfd -.RI ( newdirfd ) -is neither -.B AT_FDCWD -nor a valid file descriptor. -.TP -.B EINVAL -An invalid flag value was specified in -.IR flags . -.TP -.B ENOENT -.B AT_EMPTY_PATH -was specified in -.IR flags , -but the caller did not have the -.B CAP_DAC_READ_SEARCH -capability. -.TP -.B ENOENT -An attempt was made to link to the -.I /proc/self/fd/NN -file corresponding to a file descriptor created with -.IP -.in +4n -.EX -open(path, O_TMPFILE | O_EXCL, mode); -.EE -.in -.IP -See -.BR open (2). -.TP -.B ENOENT -An attempt was made to link to a -.I /proc/self/fd/NN -file corresponding to a file that has been deleted. -.TP -.B ENOENT -.I oldpath -is a relative pathname and -.I olddirfd -refers to a directory that has been deleted, -or -.I newpath -is a relative pathname and -.I newdirfd -refers to a directory that has been deleted. -.TP -.B ENOTDIR -.I oldpath -is relative and -.I olddirfd -is a file descriptor referring to a file other than a directory; -or similar for -.I newpath -and -.I newdirfd -.TP -.B EPERM -.B AT_EMPTY_PATH -was specified in -.IR flags , -.I oldpath -is an empty string, and -.I olddirfd -refers to a directory. -.SH VERSIONS -POSIX.1-2001 says that -.BR link () -should dereference -.I oldpath -if it is a symbolic link. -However, since Linux 2.0, -.\" more precisely: since Linux 1.3.56 -Linux does not do so: if -.I oldpath -is a symbolic link, then -.I newpath -is created as a (hard) link to the same symbolic link file -(i.e., -.I newpath -becomes a symbolic link to the same file that -.I oldpath -refers to). -Some other implementations behave in the same manner as Linux. -.\" For example, the default Solaris compilation environment -.\" behaves like Linux, and contributors to a March 2005 -.\" thread in the Austin mailing list reported that some -.\" other (System V) implementations did/do the same -- MTK, Apr 05 -POSIX.1-2008 changes the specification of -.BR link (), -making it implementation-dependent whether or not -.I oldpath -is dereferenced if it is a symbolic link. -For precise control over the treatment of symbolic links when -creating a link, use -.BR linkat (). -.SS glibc -On older kernels where -.BR linkat () -is unavailable, the glibc wrapper function falls back to the use of -.BR link (), -unless the -.B AT_SYMLINK_FOLLOW -is specified. -When -.I oldpath -and -.I newpath -are relative pathnames, -glibc constructs pathnames based on the symbolic links in -.I /proc/self/fd -that correspond to the -.I olddirfd -and -.I newdirfd -arguments. -.SH STANDARDS -.TP -.BR link () -POSIX.1-2008. -.SH HISTORY -.TP -.BR link () -SVr4, 4.3BSD, POSIX.1-2001 (but see VERSIONS). -.\" SVr4 documents additional ENOLINK and -.\" EMULTIHOP error conditions; POSIX.1 does not document ELOOP. -.\" X/OPEN does not document EFAULT, ENOMEM or EIO. -.TP -.BR linkat () -POSIX.1-2008. -Linux 2.6.16, -glibc 2.4. -.SH NOTES -Hard links, as created by -.BR link (), -cannot span filesystems. -Use -.BR symlink (2) -if this is required. -.SH BUGS -On NFS filesystems, the return code may be wrong in case the NFS server -performs the link creation and dies before it can say so. -Use -.BR stat (2) -to find out if the link got created. -.SH SEE ALSO -.BR ln (1), -.BR open (2), -.BR rename (2), -.BR stat (2), -.BR symlink (2), -.BR unlink (2), -.BR path_resolution (7), -.BR symlink (7) |