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+.\" Copyright (c) 1988, 1991, 1993
+.\" The Regents of the University of California. All rights reserved.
+.\"
+.\" This code is derived from software contributed to Berkeley by
+.\" the American National Standards Committee X3, on Information
+.\" Processing Systems.
+.\"
+.\" 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.
+.\" 4. 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.
+.\"
+.\" @(#)tmpnam.3 8.2 (Berkeley) 11/17/93
+.\" $FreeBSD$
+.\"
+.Dd March 18, 2007
+.Dt TMPFILE 3
+.Os
+.Sh NAME
+.Nm tempnam ,
+.Nm tmpfile ,
+.Nm tmpnam
+.Nd temporary file routines
+.Sh LIBRARY
+.Lb libc
+.Sh SYNOPSIS
+.In stdio.h
+.Ft FILE *
+.Fn tmpfile void
+.Ft char *
+.Fn tmpnam "char *str"
+.Ft char *
+.Fn tempnam "const char *tmpdir" "const char *prefix"
+.Sh DESCRIPTION
+The
+.Fn tmpfile
+function
+returns a pointer to a stream associated with a file descriptor returned
+by the routine
+.Xr mkstemp 3 .
+The created file is unlinked before
+.Fn tmpfile
+returns, causing the file to be automatically deleted when the last
+reference to it is closed.
+The file is opened with the access value
+.Ql w+ .
+The file is created in the directory determined by the environment variable
+.Ev TMPDIR
+if set.
+The default location if
+.Ev TMPDIR
+is not set is
+.Pa /tmp .
+.Pp
+The
+.Fn tmpnam
+function
+returns a pointer to a file name, in the
+.Dv P_tmpdir
+directory, which
+did not reference an existing file at some indeterminate point in the
+past.
+.Dv P_tmpdir
+is defined in the include file
+.In stdio.h .
+If the argument
+.Fa str
+is
+.Pf non- Dv NULL ,
+the file name is copied to the buffer it references.
+Otherwise, the file name is copied to a static buffer.
+In either case,
+.Fn tmpnam
+returns a pointer to the file name.
+.Pp
+The buffer referenced by
+.Fa str
+is expected to be at least
+.Dv L_tmpnam
+bytes in length.
+.Dv L_tmpnam
+is defined in the include file
+.In stdio.h .
+.Pp
+The
+.Fn tempnam
+function
+is similar to
+.Fn tmpnam ,
+but provides the ability to specify the directory which will
+contain the temporary file and the file name prefix.
+.Pp
+The environment variable
+.Ev TMPDIR
+(if set), the argument
+.Fa tmpdir
+(if
+.Pf non- Dv NULL ) ,
+the directory
+.Dv P_tmpdir ,
+and the directory
+.Pa /tmp
+are tried, in the listed order, as directories in which to store the
+temporary file.
+.Pp
+The argument
+.Fa prefix ,
+if
+.Pf non- Dv NULL ,
+is used to specify a file name prefix, which will be the
+first part of the created file name.
+The
+.Fn tempnam
+function
+allocates memory in which to store the file name; the returned pointer
+may be used as a subsequent argument to
+.Xr free 3 .
+.Sh RETURN VALUES
+The
+.Fn tmpfile
+function
+returns a pointer to an open file stream on success, and a
+.Dv NULL
+pointer
+on error.
+.Pp
+The
+.Fn tmpnam
+and
+.Fn tempfile
+functions
+return a pointer to a file name on success, and a
+.Dv NULL
+pointer
+on error.
+.Sh ENVIRONMENT
+.Bl -tag -width Ds
+.It Ev TMPDIR
+.Pf [ Fn tempnam
+only]
+If set,
+the directory in which the temporary file is stored.
+.Ev TMPDIR
+is ignored for processes
+for which
+.Xr issetugid 2
+is true.
+.El
+.Sh COMPATIBILITY
+These interfaces are provided from System V and
+.Tn ANSI
+compatibility only.
+.Pp
+Most historic implementations of these functions provide
+only a limited number of possible temporary file names
+(usually 26)
+before file names will start being recycled.
+System V implementations of these functions
+(and of
+.Xr mktemp 3 )
+use the
+.Xr access 2
+system call to determine whether or not the temporary file
+may be created.
+This has obvious ramifications for setuid or setgid programs,
+complicating the portable use of these interfaces in such programs.
+.Pp
+The
+.Fn tmpfile
+interface should not be used in software expected to be used on other systems
+if there is any possibility that the user does not wish the temporary file to
+be publicly readable and writable.
+.Sh ERRORS
+The
+.Fn tmpfile
+function
+may fail and set the global variable
+.Va errno
+for any of the errors specified for the library functions
+.Xr fdopen 3
+or
+.Xr mkstemp 3 .
+.Pp
+The
+.Fn tmpnam
+function
+may fail and set
+.Va errno
+for any of the errors specified for the library function
+.Xr mktemp 3 .
+.Pp
+The
+.Fn tempnam
+function
+may fail and set
+.Va errno
+for any of the errors specified for the library functions
+.Xr malloc 3
+or
+.Xr mktemp 3 .
+.Sh SEE ALSO
+.Xr mkstemp 3 ,
+.Xr mktemp 3
+.Sh STANDARDS
+The
+.Fn tmpfile
+and
+.Fn tmpnam
+functions
+conform to
+.St -isoC .
+.Sh SECURITY CONSIDERATIONS
+The
+.Fn tmpnam
+and
+.Fn tempnam
+functions are susceptible to a race condition
+occurring between the selection of the file name
+and the creation of the file,
+which allows malicious users
+to potentially overwrite arbitrary files in the system,
+depending on the level of privilege of the running program.
+Additionally, there is no means by which
+file permissions may be specified.
+It is strongly suggested that
+.Xr mkstemp 3
+be used in place of these functions.
+(See
+the FSA.)
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