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Diffstat (limited to 'static/netbsd/man2/readlink.2')
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diff --git a/static/netbsd/man2/readlink.2 b/static/netbsd/man2/readlink.2 new file mode 100644 index 00000000..910900db --- /dev/null +++ b/static/netbsd/man2/readlink.2 @@ -0,0 +1,177 @@ +.\" $NetBSD: readlink.2,v 1.33 2017/07/03 21:32:50 wiz Exp $ +.\" +.\" Copyright (c) 1983, 1991, 1993 +.\" The Regents of the University of California. All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" 3. Neither the name of the University nor the names of its contributors +.\" may be used to endorse or promote products derived from this software +.\" without specific prior written permission. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" @(#)readlink.2 8.1 (Berkeley) 6/4/93 +.\" +.Dd July 28, 2013 +.Dt READLINK 2 +.Os +.Sh NAME +.Nm readlink , +.Nm readlinkat +.Nd read value of a symbolic link +.Sh LIBRARY +.Lb libc +.Sh SYNOPSIS +.In unistd.h +.Ft ssize_t +.Fn readlink "const char * restrict path" "char * restrict buf" "size_t bufsiz" +.Ft ssize_t +.Fn readlinkat "int fd" "const char * restrict path" "char * restrict buf"\ + "size_t bufsiz" +.Sh DESCRIPTION +.Fn readlink +places the contents of the symbolic link +.Fa path +in the buffer +.Fa buf , +which has size +.Fa bufsiz . +.Fn readlink +does not append a +.Dv NUL +character to +.Fa buf . +.Pp +.Fn readlinkat +works the same way as +.Fn readlink +except if +.Fa path +is relative. +In that case, it is looked up from a directory whose file +descriptor was passed as +.Fa fd . +Search permission is required on this directory. +.\" (These alternatives await a decision about the semantics of O_SEARCH) +.\" Search permission is required on this directory +.\" except if +.\" .Fa fd +.\" was opened with the +.\" .Dv O_SEARCH +.\" flag. +.\" - or - +.\" This file descriptor must have been opened with the +.\" .Dv O_SEARCH +.\" flag. +.Fa fd +can be set to +.Dv AT_FDCWD +in order to specify the current directory. +.Sh RETURN VALUES +The call returns the count of characters placed in the buffer +if it succeeds, or a \-1 if an error occurs, placing the error +code in the global variable +.Va errno . +.Sh EXAMPLES +A typical use is illustrated in the following piece of code +which reads the contents of a symbolic link named +.Pa /symbolic/link +and stores them as null-terminated string: +.Bd -literal -offset indent +#include <limits.h> +#include <unistd.h> + +char buf[PATH_MAX]; +ssize_t len; + +if ((len = readlink("/symbolic/link", buf, sizeof(buf)-1)) == -1) + error handling; +buf[len] = '\e0'; +.Ed +.Sh ERRORS +.Fn readlink +and +.Fn readlinkat +will fail if: +.Bl -tag -width Er +.It Bq Er EACCES +Search permission is denied for a component of the path prefix. +.It Bq Er EFAULT +.Fa buf +extends outside the process's allocated address space. +.It Bq Er EINVAL +The named file is not a symbolic link. +.It Bq Er EIO +An I/O error occurred while reading from the file system. +.It Bq Er ELOOP +Too many symbolic links were encountered in translating the pathname. +.It Bq Er ENAMETOOLONG +A component of a pathname exceeded +.Brq Dv NAME_MAX +characters, or an entire path name exceeded +.Brq Dv PATH_MAX +characters. +.It Bq Er ENOENT +The named file does not exist. +.It Bq Er ENOTDIR +A component of the path prefix is not a directory. +.El +.Pp +In addition, +.Fn readlinkat +will fail if: +.Bl -tag -width Er +.It Bq Er EBADF +.Fa path +does not specify an absolute path and +.Fa fd +is neither +.Dv AT_FDCWD +nor a valid file descriptor open for reading or searching. +.It Bq Er ENOTDIR +.Fa path +is not an absolute path and +.Fa fd +is a file descriptor associated with a non-directory file. +.El +.Sh SEE ALSO +.Xr lstat 2 , +.Xr stat 2 , +.Xr symlink 2 , +.Xr symlink 7 +.Sh STANDARDS +The +.Fn readlink +function conforms to +.St -p1003.1-2001 . +.Fn readlinkat +conforms to +.St -p1003.1-2008 . +.Sh HISTORY +The +.Fn readlink +function appeared in +.Bx 4.2 . +The type returned was changed from +.Ft int +to +.Ft ssize_t +in +.Nx 2.1 . |