SUNWbnuu
Note: For security reasons, most installations limit the list of commands executable on behalf of an incoming request from uux, permitting only the receipt of mail (see mail(1) ). (Remote execution permissions are defined in /etc/uucp/Permissions.)
The command-string is made up of one or more arguments that look like a shell command line, except that the command and file names may be prefixed by system-name!. A null system-name is interpreted as the local system.
File names may be one of the following:
- An absolute path name.
- A path name preceded by ~xxx, where xxx is a login name on the specified system and is replaced by that user’s login directory.
Anything else is prefixed by the current directory.
As an example, the command:
example% uux "!diff sys1!/home/dan/filename1 sys2!/a4/dan/filename2 > !~/dan/filename.diff"
will get the filename1 and filename2 files from the ‘‘sys1’’ and ‘‘sys2’’ machines, execute a diff(1) command and put the results in filename.diff in the local PUBDIR/dan/ directory. PUBDIR is a public directory defined in the uucp source. By default, this directory is /var/spool/uucppublic.
Any special shell characters such as <, >, ;, | should be quoted either by quoting the entire command-string, or quoting the special characters as individual arguments. The redirection operators >>, <<, >| and >& cannot be used.
uux will attempt to get all appropriate files to the specified system where they will be processed. For files that are output files, the file name must be escaped using parentheses. For example, the command:
example% uux "a!cut -f1 b!/usr/filename > c!/usr/filename"
gets "/usr/filename" from system "b" and sends it to system "a", performs a cut command on that file and sends the result of the cut command to system "c".
uux will notify you if the requested command on the remote system
was disallowed. This notification can be turned off by the -n option. The
response comes by remote mail from the remote machine.
All files required for the execution will be put into this directory unless they already reside on that machine. Therefore, the simple file name (without path or machine reference) must be unique within the uux request. The following command will NOT work:
example% uux "a!diff b!/home/dan/xyz c!/home/dan/xyz > !xyz.diff"
But the command:
example% uux "a!diff a!/home/dan/xyz c!/home/dan/xyz > !xyz.diff"
will work. (If diff is a permitted command.)
Protected files and files that are in protected directories that are owned by the requester can be sent in commands using uux. However, if the requester is root, and the directory is not searchable by "other", the request will fail.
The following restrictions apply to the shell pipeline processed by uux:
- In gathering files from different systems, pathname expansion in not performed by uux. Thus, a request such as
uux "c89 remsys!~/*.c"would attempt to copy the file named literally *.c to the local system.
- Only the first command of a shell pipeline may have a system-name!. All other commands are executed on the system of the first command.
- The use of the shell metacharacter * will probably not do what you want it to do.
- The shell tokens << and >> are not implemented.
- The redirection operators >>, <<, >| and >& cannot be used.
- The reserved word ! cannot be used at the head of the pipeline to modify the exit status.
- Alias substitution is not performed.