.\"
.\" Copyright (c) 2005-2019
.\"	Jeffrey Allen Neitzel <jan (at) etsh (dot) nl>.
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.\"	@(#)$Id: fd2.1,v 1.5 2019/03/14 08:50:46 jneitzel Exp $
.\"
.\" Includes public domain content derived from:
.\"		- /usr/src/bin/ksh/sh.1
.\"			$OpenBSD: sh.1,v 1.91 2011/09/03 22:59:08 jmc Exp $
.\"
.TH FD2 1 "@ETSH_DATE@" "@ETSH_VERSION@" "General Commands Manual"
.SH NAME
fd2 \- redirect from/to file descriptor 2
.SH SYNOPSIS
.B fd2
[\fB\-e\fR] [\fB\-f\fR \fIfile\fR] [\fB\-\-\fR] \fIcommand\fR [\fIarg ...\fR]
.SH DESCRIPTION
Since the Version 6 (V6) UNIX shell provides
no way to redirect the diagnostic output,
.B fd2
makes this possible by executing the specified
.I command
with the given arguments
and redirecting file descriptor 2 (standard error)
to file descriptor 1 (standard output) by default.
.PP
The options are as follows:
.TP
.B \-e
Causes all conventional output from
.I command
to be redirected to the standard error
as diagnostic output.
.TP
.BI \-f " file"
Causes all diagnostic output from
.I command
to be redirected to \fIfile\fR,
which is created if it does not exist.
If it already exists,
all diagnostic output is appended
to the end of \fIfile\fR.
.TP
.B \-\-
Causes
.B fd2
to stop further option processing,
forcing it to treat all following arguments
as \fIcommand\fR [\fIarg ...\fR] .
.SH "EXIT STATUS"
If
.B fd2
detects an error,
it prints an appropriate diagnostic
and exits with a non-zero status.
Otherwise,
the exit status is that
of the executed command.
.SH ENVIRONMENT
.TP
.B EXECSHELL
If set to a non-empty string,
the value of this variable is taken as the
path name of the shell which is invoked to
execute the specified command when it does not
begin with the proper magic number
or a `#!shell' sequence.
.TP
.B PATH
If set to a non-empty string,
the value of this variable is taken as the
sequence of directories which is used to
search for the specified command.
.SH EXAMPLES
The examples below which refer to `/tmp/$$' assume
that this directory exists and is writable by the user.
The following command line:
.PP
.RS 6
fd2 \-e echo progname: Error message
.RE
.PP
causes all conventional output from
.I echo
to be redirected to the standard error
as diagnostic output.
The following command line:
.PP
.RS 6
fd2 make foo >/tmp/$$/foo.outerr
.RE
.PP
causes all conventional and diagnostic output from
.I make
to be redirected to the file `/tmp/$$/foo.outerr',
which is first created by the shell.
In contrast:
.PP
.RS 6
fd2 \-f /tmp/$$/foo.err make foo >/tmp/$$/foo.out
.RE
.PP
causes all conventional output to be redirected
to the file `/tmp/$$/foo.out',
which is created by the shell.
All diagnostic output is redirected
to the file `/tmp/$$/foo.err',
which is created by
.B fd2
if it does not already exist.
.SH "SEE ALSO"
@EBN@(1),
@TBN@(1)
.PP
Etsh home page:
https://etsh.nl/
.SH AUTHOR
Jeffrey Allen Neitzel
.RI < jan@etsh.nl >
wrote this implementation of the
.B fd2
command and maintains it as
.IR fd2 (1).
.SH LICENSE
See either the LICENSE file which is distributed with
.B @EBN@
or
https://etsh.nl/license/
for full details.