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Full Discussion: Fighting useless use of cat
The Lounge What is on Your Mind? Fighting useless use of cat Post 302782115 by drl on Monday 18th of March 2013 09:31:30 AM
Old 03-18-2013
Hi.
Quote:
Originally Posted by MadeInGermany
...
Logically, the same should apply ...
The documentation says:
Code:
REDIRECTION
       Before a command is executed, its input and output may be redirected
       using a special notation interpreted by the shell.  Redirection may
       also be used to open and close files for the current shell execution
       environment.  The following redirection operators may precede or appear
       anywhere within a simple command or may follow a command.  Redirections
       are processed in the order they appear, from left to right.

-- excerpt from man bash

Because the statement in question is not a simple command, then syntax, design, and code prevail over what may seem logical.

I note that ksh and dash also fail to process as you desire, but, I agree, zsh seems OK with the short tests I did.

Best wishes ... cheers, drl

( Edit 1: grammar correction )

Last edited by drl; 03-18-2013 at 11:32 AM..
 

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RBASH(1)						      General Commands Manual							  RBASH(1)

NAME
rbash - restricted bash, see bash(1) RESTRICTED SHELL
If bash is started with the name rbash, or the -r option is supplied at invocation, the shell becomes restricted. A restricted shell is used to set up an environment more controlled than the standard shell. It behaves identically to bash with the exception that the follow- ing are disallowed or not performed: o changing directories with cd o setting or unsetting the values of SHELL, PATH, ENV, or BASH_ENV o specifying command names containing / o specifying a file name containing a / as an argument to the . builtin command o specifying a filename containing a slash as an argument to the -p option to the hash builtin command o importing function definitions from the shell environment at startup o parsing the value of SHELLOPTS from the shell environment at startup o redirecting output using the >, >|, <>, >&, &>, and >> redirection operators o using the exec builtin command to replace the shell with another command o adding or deleting builtin commands with the -f and -d options to the enable builtin command o using the enable builtin command to enable disabled shell builtins o specifying the -p option to the command builtin command o turning off restricted mode with set +r or set +o restricted. These restrictions are enforced after any startup files are read. When a command that is found to be a shell script is executed, rbash turns off any restrictions in the shell spawned to execute the script. SEE ALSO
bash(1) GNU Bash-4.0 2004 Apr 20 RBASH(1)
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