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Full Discussion: Bash script undesired output
Top Forums Shell Programming and Scripting Bash script undesired output Post 302224710 by bakunin on Wednesday 13th of August 2008 08:21:29 PM
Old 08-13-2008
Quote:
Originally Posted by Smiling Dragon
Using $() instead of the 'old fashioned backticks' won't work on bourne though Smilie
True, but AFAIK Bourne Shell is a bit outdated by now - this is what i meant by "oldfashioned". Its similar to using mono-character variable names in programs because FORTRAN/77 didn't honour more than 6 characters of an identifier. This might be, but nobody in his right mind would use a compiler which is more than 30 years old today.

Quote:
How come they shouldn't be used anymore BTW (geniune question, not stirring like my first comment was Smilie)?
In Korn-Shell, bash and most other modern shells the "$(...)" construct offers more flexibility and better readability (backticks are easily confused with single quotes as several threads here show) and better functionality. The reason why backticks are still working in these shells is not because the authors thought these were desirable but for backward compatibility. This is not a reason to still use them, even more so as the threadstarter seems to be learning shell scripting and should adopt proper practices as early as possible.

For an in-depth discussion about backticks see Barry Rosenbergs "Hands-On ksh93 Programming" or have a look here or take into account that backticks cannot be nested whereas "$(...)" can be, etc..

bakunin
 

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LEARN ABOUT DEBIAN

acorn-fdisk

FDISK(8)						    BSD System Manager's Manual 						  FDISK(8)

NAME

     acorn-fdisk -- partition editor for Acorn/RISC OS machines

SYNOPSIS

     acorn-fdisk -h | --help | -v | --version

     acorn-fdisk [-t scheme | --type scheme] -l | --list [device ...]

     acorn-fdisk [-t scheme | --type scheme] -s | --size partition

     acorn-fdisk [-t scheme | --type scheme] [device]

DESCRIPTION

     The acorn-fdisk utility allows one to display or interactively edit partition tables for Acorn/RISC OS machines in various formats.  Using
     the PC/BIOS format, standard IBM PC (i386) partition tables can also be accessed.	When no optional device is given, it defaults to /dev/hda
     or /dev/sda.

     The options are as follows:

     -h | --help  Display a short usage and exit immediately.

     -l | --list  Display the partition table(s) of all devices.

     -s | --size  Display the size of partition.

     -t | --type  Select the partitioning scheme to use.  Valid schemes are:

		  EESOX 	   Eesox SCSI on the Acorn machines.

		  ICSIDEFS	   ICS IDE.

		  Filecore/Linux   Linux on Filecore.  This uses the non-ADFS descriptor to point to the start of the disc to be partitioned.  The
				   first two sectors contain a partition table to identify the Linux partitions contained within.

		  PC/BIOS	   PC/BIOS partitioning scheme.  This consists of a partition table in the first sector of the disk which contains
				   both CHS and LBA values for the partitions.	There can be up to four entries in the primary partition table.
				   One of these can be an extended partition containing up to four extra partitions.

		  PowerTec	   PowerTec SCSI on the Acorn machines.

		  Filecore/RISCiX  RiscIX on Filecore.

     -v | --version
		  Display the version of acorn-fdisk and exit immediately.

     If neither -l | --list or -s | --size are given, the partition table of the given device will be edited interactively.

EXAMPLES

     Display the default device's partition table on a PC:

	   acorn-fdisk --type PC/BIOS -l

     Display the PC partition table of /dev/sda:

	   acorn-fdisk --type PC/BIOS --list /dev/sda

     Display the size in blocks of the partition /dev/sda1:

	   acorn-fdisk --type PC/BIOS --size /dev/sda1

     Edit the MBR partition table interactively:

	   acorn-fdisk --type PC/BIOS

     Display the partition table of an MBR backed up to a file:

	   acorn-fdisk -t PC/BIOS -l mbrdump.bin

     Display the size of the first partition on a device where the MBR would be restored from the backup file mbrdump.bin:

	   acorn-fdisk -t PC/BIOS -s mbrdump.bin1

AUTHORS

     arm-fdisk was written by Russell King <rmk@arm.uk.linux.org> based on util-linux fdisk, which was written at least partially by
     A. V. Le Blanc <LeBlanc@mcc.ac.uk>.

     This manual page was written for the Debian system by
     Thorsten Glaser <tg@debian.org> but may be used by others.

BSD
								  October 2, 2010							       BSD
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