c499f23b6e
PR: docs/95059 Submitted by: Jos Backus MFC after: 4 days
207 lines
4.9 KiB
Groff
207 lines
4.9 KiB
Groff
.\"
|
|
.\" Copyright (c) 2002 Tim J. Robbins
|
|
.\" 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.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
|
|
.\"
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.Dd July 29, 2004
|
|
.Dt WORDEXP 3
|
|
.Os
|
|
.Sh NAME
|
|
.Nm wordexp
|
|
.Nd "perform shell-style word expansions"
|
|
.Sh LIBRARY
|
|
.Lb libc
|
|
.Sh SYNOPSIS
|
|
.In wordexp.h
|
|
.Ft int
|
|
.Fn wordexp "const char * restrict words" "wordexp_t * restrict we" "int flags"
|
|
.Ft void
|
|
.Fn wordfree "wordexp_t *we"
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Fn wordexp
|
|
function performs shell-style word expansion on
|
|
.Fa words
|
|
and places the list of words into the
|
|
.Va we_wordv
|
|
member of
|
|
.Fa we ,
|
|
and the number of words into
|
|
.Va we_wordc .
|
|
.Pp
|
|
The
|
|
.Fa flags
|
|
argument is the bitwise inclusive OR of any of the following constants:
|
|
.Bl -tag -width ".Dv WRDE_SHOWERR"
|
|
.It Dv WRDE_APPEND
|
|
Append the words to those generated by a previous call to
|
|
.Fn wordexp .
|
|
.It Dv WRDE_DOOFFS
|
|
As many
|
|
.Dv NULL
|
|
pointers as are specified by the
|
|
.Va we_offs
|
|
member of
|
|
.Fa we
|
|
are added to the front of
|
|
.Va we_wordv .
|
|
.It Dv WRDE_NOCMD
|
|
Disallow command substitution in
|
|
.Fa words .
|
|
See the note in
|
|
.Sx BUGS
|
|
before using this.
|
|
.It Dv WRDE_REUSE
|
|
The
|
|
.Fa we
|
|
argument was passed to a previous successful call to
|
|
.Fn wordexp
|
|
but has not been passed to
|
|
.Fn wordfree .
|
|
The implementation may reuse the space allocated to it.
|
|
.It Dv WRDE_SHOWERR
|
|
Do not redirect shell error messages to
|
|
.Pa /dev/null .
|
|
.It Dv WRDE_UNDEF
|
|
Report error on an attempt to expand an undefined shell variable.
|
|
.El
|
|
.Pp
|
|
The
|
|
.Vt wordexp_t
|
|
structure is defined in
|
|
.In wordexp.h
|
|
as:
|
|
.Bd -literal -offset indent
|
|
typedef struct {
|
|
size_t we_wordc; /* count of words matched */
|
|
char **we_wordv; /* pointer to list of words */
|
|
size_t we_offs; /* slots to reserve in we_wordv */
|
|
} wordexp_t;
|
|
.Ed
|
|
.Pp
|
|
The
|
|
.Fn wordfree
|
|
function frees the memory allocated by
|
|
.Fn wordexp .
|
|
.Sh IMPLEMENTATION NOTES
|
|
The
|
|
.Fn wordexp
|
|
function is implemented as a wrapper around the undocumented
|
|
.Ic wordexp
|
|
shell built-in command.
|
|
.Sh RETURN VALUES
|
|
The
|
|
.Fn wordexp
|
|
function returns zero if successful, otherwise it returns one of the following
|
|
error codes:
|
|
.Bl -tag -width ".Dv WRDE_NOSPACE"
|
|
.It Dv WRDE_BADCHAR
|
|
The
|
|
.Fa words
|
|
argument contains one of the following unquoted characters:
|
|
.Aq newline ,
|
|
.Ql | ,
|
|
.Ql & ,
|
|
.Ql \&; ,
|
|
.Ql < ,
|
|
.Ql > ,
|
|
.Ql \&( ,
|
|
.Ql \&) ,
|
|
.Ql { ,
|
|
.Ql } .
|
|
.It Dv WRDE_BADVAL
|
|
An attempt was made to expand an undefined shell variable and
|
|
.Dv WRDE_UNDEF
|
|
is set in
|
|
.Fa flags .
|
|
.It Dv WRDE_CMDSUB
|
|
An attempt was made to use command substitution and
|
|
.Dv WRDE_NOCMD
|
|
is set in
|
|
.Fa flags .
|
|
.It Dv WRDE_NOSPACE
|
|
Not enough memory to store the result.
|
|
.It Dv WRDE_SYNTAX
|
|
Shell syntax error in
|
|
.Fa words .
|
|
.El
|
|
.Pp
|
|
The
|
|
.Fn wordfree
|
|
function returns no value.
|
|
.Sh ENVIRONMENT
|
|
.Bl -tag -width ".Ev IFS"
|
|
.It Ev IFS
|
|
Field separator.
|
|
.El
|
|
.Sh EXAMPLES
|
|
Invoke the editor on all
|
|
.Pa .c
|
|
files in the current directory
|
|
and
|
|
.Pa /etc/motd
|
|
(error checking omitted):
|
|
.Bd -literal -offset indent
|
|
wordexp_t we;
|
|
|
|
wordexp("${EDITOR:-vi} *.c /etc/motd", &we, 0);
|
|
execvp(we.we_wordv[0], we.we_wordv);
|
|
.Ed
|
|
.Sh DIAGNOSTICS
|
|
Diagnostic messages from the shell are written to the standard error output
|
|
if
|
|
.Dv WRDE_SHOWERR
|
|
is set in
|
|
.Fa flags .
|
|
.Sh SEE ALSO
|
|
.Xr sh 1 ,
|
|
.Xr fnmatch 3 ,
|
|
.Xr glob 3 ,
|
|
.Xr popen 3 ,
|
|
.Xr system 3
|
|
.Sh STANDARDS
|
|
The
|
|
.Fn wordexp
|
|
and
|
|
.Fn wordfree
|
|
functions conform to
|
|
.St -p1003.1-2001 .
|
|
.Sh BUGS
|
|
Do not pass untrusted user data to
|
|
.Fn wordexp ,
|
|
regardless of whether the
|
|
.Dv WRDE_NOCMD
|
|
flag is set.
|
|
The
|
|
.Fn wordexp
|
|
function attempts to detect input that would cause commands to be
|
|
executed before passing it to the shell
|
|
but it does not use the same parser so it may be fooled.
|
|
.Pp
|
|
The current
|
|
.Fn wordexp
|
|
implementation does not recognize multibyte characters, since the
|
|
shell (which it invokes to perform expansions) does not.
|