01-30-2017
Lets not get deep into subshells.
I'm sure you experts don't have too many nested subshells in your code
In my opinion, it lowers the control you have in your program.
So if you have small, efficient script with no nested subshells, are backquotes still the lowest denominator e.g will it run without magic cookie on any unix OS ever produced ?
Example would be a simple mv script using basename command in subshell.
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Can someone explain the difference between backticks and system when
evaluated in these if statements:
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start date
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Hi,
I would like to change some lines in my mysql-dump, because there a syntax problems with some version of mysql.
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USE ´someDatabase´;
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Hey all. Just a fast question, what is the technical difference between using back ticks and using xargs to perform a command?
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Input file:
'data_1'
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data_1
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data1311
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fileutil::magic::cgen(n) file utilities fileutil::magic::cgen(n)
__________________________________________________________________________________________________________________________________________________
NAME
fileutil::magic::cgen - Generator core for compiler of magic(5) files
SYNOPSIS
package require Tcl 8.4
package require fileutil::magic::cgen ?1.0?
package require fileutil::magic::rt ?1.0?
package require struct::tree
package require struct::list
::fileutil::magic::cgen::2tree script
::fileutil::magic::cgen::treedump tree
::fileutil::magic::cgen::treegen tree node
_________________________________________________________________
DESCRIPTION
This package provides the generator backend for a compiler of magic(5) files into recognizers based on the fileutil::magic::rt recognizer
runtime package. For the compiler frontend using this generator see the package fileutil::magic::cfront.
COMMANDS
::fileutil::magic::cgen::2tree script
This command converts the recognizer specified by the script into a tree and returns the object command of that tree as its result.
It uses the package struct::tree for the tree.
The script is in the format specified by magic(5).
::fileutil::magic::cgen::treedump tree
This command takes a tree as generated by ::fileutil::magic::cgen::2tree and returns a string encoding the tree for human consump-
tion, to aid in debugging.
::fileutil::magic::cgen::treegen tree node
This command takes a tree as generated by ::fileutil::magic::cgen::2tree and returns a Tcl script, the recognizer for the file types
represented by the sub-tree rooted at the node. The generated script makes extensive use of the commands provided by the recognizer
runtime package fileutil::magic::rt to perform its duties.
BUGS, IDEAS, FEEDBACK
This document, and the package it describes, will undoubtedly contain bugs and other problems. Please report such in the category fileutil
:: magic of the Tcllib SF Trackers [http://sourceforge.net/tracker/?group_id=12883]. Please also report any ideas for enhancements you may
have for either package and/or documentation.
SEE ALSO
file(1), fileutil, magic(5)
KEYWORDS
file recognition, file type, file utilities, mime, type
CATEGORY
Programming tools
fumagic 1.0 fileutil::magic::cgen(n)