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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print "start date\n";
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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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I'm always concerned I might be abusing backticks within my scripts. A current script I'm writing has this for example:
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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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LEARN ABOUT MOJAVE
cfront
fileutil::magic::cfront(n) file utilities fileutil::magic::cfront(n)
__________________________________________________________________________________________________________________________________________________
NAME
fileutil::magic::cfront - Generator core for compiler of magic(5) files
SYNOPSIS
package require Tcl 8.4
package require fileutil::magic::cfront ?1.0?
package require fileutil::magic::cgen ?1.0?
package require fileutil::magic::rt ?1.0?
package require struct::list
package require fileutil
::fileutil::magic::cfront::compile path...
::fileutil::magic::cfront::procdef procname path...
::fileutil::magic::cfront::install path...
_________________________________________________________________
DESCRIPTION
This package provides the frontend of a compiler of magic(5) files into recognizers based on the fileutil::magic::rt recognizer runtime
package. For the generator backed used by this compiler see the package fileutil::magic::cgen.
COMMANDS
::fileutil::magic::cfront::compile path...
This command takes the paths of one or more files and directories and compiles all the files, and the files in all the directories
into a single recognizer for all the file types specified in these files.
All the files have to be in the format specified by magic(5).
The result of the command is a Tcl script containing the generated recognizer.
::fileutil::magic::cfront::procdef procname path...
This command behaves like ::fileutil::magic::cfront::compile with regard to the specified path arguments, then wraps the resulting
recognizer script into a procedure named procname, puts code setting up the namespace of procname in front, and returns the result-
ing script.
::fileutil::magic::cfront::install path...
This command uses ::fileutil::magic::cfront::procdef to compile each of the paths into a recognizer procedure and installs the
result in the current interpreter.
The name of each new procedure is derived from the name of the file/directory used in its creation, with file/directory "FOO" caus-
ing the creation of procedure ::fileutil::magic::/FOO::run.
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::cfront(n)