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If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner] .TH runat 1 "22 Jun 2001" "SunOS 5.11" "User Commands" .SH NAME runat \- execute command in extended attribute name space .SH SYNOPSIS .LP .nf \fB/usr/bin/runat\fR \fIfile\fR [\fIcommand\fR] .fi .SH DESCRIPTION .sp .LP The \fBrunat\fR utility is used to execute shell commands in a file's hidden attribute directory. Effectively, this utility changes the current working directory to be the hidden attribute directory associated with the file argument and then executes the specified command in the bourne shell (\fB/bin/sh\fR). If no command argument is provided, an interactive shell is spawned. The environment variable $\fBSHELL\fR defines the shell to be spawned. If this variable is undefined, the default shell, \fB/bin/sh\fR, is used. .sp .LP The file argument can be any file, including a directory, that can support extended attributes. It is not necessary that this file have any attributes, or be prepared in any way, before invoking the \fBrunat\fR command. .SH OPERANDS .sp .LP The following operands are supported: .sp .ne 2 .mk .na \fB\fIfile\fR\fR .ad .RS 12n .rt Any file, including a directory, that can support extended attributes. .RE .sp .ne 2 .mk .na \fB\fIcommand\fR \fR .ad .RS 12n .rt The command to be executed in an attribute directory. .RE .SH ERRORS .sp .LP A non-zero exit status will be returned if \fBrunat\fR cannot access the \fIfile\fR argument, or the \fIfile\fR argument does not support extended attributes. .SH USAGE .sp .LP See \fBfsattr\fR(5) for a detailed description of extended file attributes. .sp .LP The process context created by the \fBrunat\fR command has its current working directory set to the hidden directory containing the file's extended attributes. The parent of this directory (the "\fB\&..\fR" entry) always refers to the file provided on the command line. As such, it may not be a directory. Therefore, commands (such as \fBpwd\fR) that depend upon the parent entry being well-formed (that is, referring to a directory) may fail. .sp .LP In the absence of the \fIcommand\fR argument, \fBrunat\fR will spawn a new interactive shell with its current working directory set to be the provided file's hidden attribute directory. Notice that some shells (such as \fBzsh\fR and \fBtcsh\fR) are not well behaved when the directory parent is not a directory, as described above. These shells should not be used with \fBrunat\fR. .SH EXAMPLES .LP \fBExample 1 \fRUsing runat to list extended attributes on a file .sp .in +2 .nf example% \fBrunat file.1 ls -l\fR example% \fBrunat file.1 ls\fR .fi .in -2 .sp .LP \fBExample 2 \fRCreating extended attributes .sp .in +2 .nf example% \fBrunat file.2 cp /tmp/attrdata attr.1\fR example% \fBrunat file.2 cat /tmp/attrdata > attr.1\fR .fi .in -2 .sp .LP \fBExample 3 \fRCopying an attribute from one file to another .sp .in +2 .nf example% \fBrunat file.2 cat attr.1 | runat file.1 "cat > attr.1"\fR .fi .in -2 .sp .LP \fBExample 4 \fRUsing runat to spawn an interactive shell .sp .in +2 .nf example% \fBrunat file.3 /bin/sh\fR .fi .in -2 .sp .sp .LP This spawns a new shell in the attribute directory for \fBfile.3\fR. Notice that the shell will not be able to determine what your current directory is. To leave the attribute directory, either exit the spawned shell or change directory (\fBcd\fR) using an absolute path. .sp .LP Recommended methods for performing basic attribute operations: .sp .ne 2 .mk .na \fBdisplay\fR .ad .RS 22n .rt \fBrunat \fIfile\fR ls [\fIoptions\fR]\fR .RE .sp .ne 2 .mk .na \fBread\fR .ad .RS 22n .rt \fBrunat \fIfile\fR cat \fIattribute\fR\fR .RE .sp .ne 2 .mk .na \fBcreate/modify\fR .ad .RS 22n .rt \fBrunat \fIfile\fR cp \fIabsolute-file-path\fR \fIattribute\fR\fR .RE .sp .ne 2 .mk .na \fBdelete\fR .ad .RS 22n .rt \fBrunat \fIfile\fR rm \fIattribute\fR\fR .RE .sp .ne 2 .mk .na \fBpermission changes\fR .ad .RS 22n .rt .sp .in +2 .nf \fBrunat \fIfile\fR chmod \fImode attribute\fR runat \fIfile\fR chgrp \fIgroup attribute\fR runat \fIfile\fR chown \fIowner attribute\fR\fR .fi .in -2 .sp .RE .sp .ne 2 .mk .na \fBinteractive shell\fR .ad .RS 22n .rt .LP .nf \fBrunat \fIfile\fR /bin/sh\fR or set your $SHELL to /bin/sh and \fBrunat \fIfile\fR\fR .fi .RE .sp .LP The above list includes commands that are known to work with \fBrunat\fR. While many other commands may work, there is no guarantee that any beyond this list will work. Any command that relies on being able to determine its current working directory is likely to fail. Examples of such commands follow: .LP \fBExample 5 \fRUsing man in an attribute directory .sp .in +2 .nf example% \fBrunat file.1 man runat\fR >getcwd: Not a directory .fi .in -2 .sp .LP \fBExample 6 \fRSpawning a tcsh shell in an attribute directory .sp .in +2 .nf example% \fBrunat file.3 /usr/bin/tcsh\fR tcsh: Not a directory tcsh: Trying to start from "/home/\fIuser\fR" .fi .in -2 .sp .sp .LP A new tcsh shell has been spawned with the current working directory set to the user's home directory. .LP \fBExample 7 \fRSpawning a zsh shell in an attribute directory .sp .in +2 .nf example% \fBrunat file.3 /usr/bin/zsh\fR example% .fi .in -2 .sp .sp .LP While the command appears to have worked, \fBzsh\fR has actually just changed the current working directory to '/'. This can be seen by using \fB/bin/pwd\fR: .sp .in +2 .nf example% \fB/bin/pwd\fR / .fi .in -2 .sp .SH ENVIRONMENT VARIABLES .sp .ne 2 .mk .na \fB\fBSHELL\fR\fR .ad .RS 9n .rt Specifies the command shell to be invoked by \fBrunat\fR. .RE .SH EXIT STATUS .sp .LP The following exit values are returned: .sp .ne 2 .mk .na \fB\fB125\fR \fR .ad .RS 8n .rt The attribute directory of the file referenced by the \fIfile\fR argument cannot be accessed. .RE .sp .ne 2 .mk .na \fB\fB126\fR \fR .ad .RS 8n .rt The exec of the provided \fIcommand\fR argument failed. .RE .sp .LP Otherwise, the exit status returned is the exit status of the shell invoked to execute the provided command. .SH ATTRIBUTES .sp .LP See \fBattributes\fR(5) for descriptions of the following attributes: .sp .sp .TS tab() box; cw(2.75i) |cw(2.75i) lw(2.75i) |lw(2.75i) . ATTRIBUTE TYPEATTRIBUTE VALUE _ CSIEnabled _ Interface StabilityEvolving .TE .SH SEE ALSO .sp .LP \fBopen\fR(2), \fBattributes\fR(5), \fBfsattr\fR(5) .SH NOTES .sp .LP It is not always obvious why a command fails in \fBrunat\fR when it is unable to determine the current working directory. The errors resulting can be confusing and ambiguous (see the \fBtcsh\fR and \fBzsh\fR examples above).