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Top Forums Shell Programming and Scripting Need help with array substitution Post 303000288 by bakunin on Saturday 8th of July 2017 07:56:13 AM
Old 07-08-2017
Quote:
Originally Posted by Scrutinizer
Actually it is the first two bytes and they inform the OS' program loader that the file is a script and that the remainder of the line specifies which command interpreter to run, with the script name as argument.
In addition it might be worth adding that only absolute pathes are allowed here. This:

Code:
#! /path/to/something

will work, whereas

Code:
#! ../../something

will not, even if ../../something would correctly resolve to the executable.

I hope this helps.

bakunin
 

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UUX(1C) 																   UUX(1C)

NAME
uux - unix to unix command execution SYNOPSIS
uux [ - ] command-string DESCRIPTION
Uux will gather 0 or more files from various systems, execute a command on a specified system and send standard output to a file on a spec- ified system. 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(1) a full pathname; (2) a pathname preceded by ~xxx; where xxx is a userid on the specified system and is replaced by that user's login directory; (3) anything else is prefixed by the current directory. The `-' option will cause the standard input to the uux command to be the standard input to the command-string. For example, the command uux "!diff usg!/usr/dan/f1 pwba!/a4/dan/f1 > !fi.diff" will get the f1 files from the usg and pwba machines, execute a diff command and put the results in f1.diff in the local directory. Any special shell characters such as <>;| should be quoted either by quoting the entire command-string, or quoting the special characters as individual arguments. FILES
/usr/uucp/spool - spool directory /usr/uucp/* - other data and programs SEE ALSO
uucp(1) D. A. Nowitz, Uucp implementation description WARNING
An installation may, and for security reasons generally will, limit the list of commands executable on behalf of an incoming request from uux. Typically, a restricted site will permit little other than the receipt of mail via uux. BUGS
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. There is no notification of denial of execution on the remote machine. UUX(1C)
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