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Full Discussion: Which cut command is more efficient?
Top Forums UNIX for Advanced & Expert Users Which cut command is more efficient? Post 302507397 by methyl on Wednesday 23rd of March 2011 06:01:56 PM
Old 03-23-2011
@Corona688
Yes, 36 cores (9x4). CPU power not an issue. Regularly running over 30,000 concurrent processes.

Bottleneck on reading large files is invariably the disc system, closely followed by the software. This is where reading moderate size files with "cat" scores over the read function in some unix utilities. I recognise that "cut" is actually one of the better ones.

For the advanced user with large data files I am not averse to using "dd" or "cpio" (or both) to read from the disc in an optimum manner.

On a single core system running ancient unix it was very important to minimise the number of concurrent processes. This is really not the case nowadays unless you happen to be running unix on a home system.

Back to the O/P.
The conventional answer is that running more processes is less efficient. On a modern large system with multiple processors (i.e. the norm) it can be more efficient to run a pipeline of multiple efficient processes than to run a single inefficient process.
The "Useless use of cat" brigade have clearly never used a modern computer where apparent inefficiencies are in fact covered by proper utilisation of the software and hardware as a team.
By applying lateral thought we can deduce that hardware design evolution is actually targetted towards making inefficient processes efficient. We can take advantage of that by tactical use of the previously-inefficent processes.

Nuff said.
Last edited by methyl; 03-23-2011 at 07:07 PM.. Reason: spellin, verbosity
 

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LEARN ABOUT OSF1

xcutsel

xcutsel(1X)															       xcutsel(1X)

NAME

       xcutsel - interchange between cut buffer and selection

SYNOPSIS

       xcutsel [-toolkitoption...] [-selection selection] [-cutbuffer number]

OPTIONS

       xcutsel	accepts  all of the standard X Toolkit command line options as well as the following: This option specifies the name of the selec-
       tion to use.  The default is PRIMARY.  The only supported abbreviations for this option are "-select", "-sel" and  "-s",  as  the  standard
       toolkit option "-selectionTimeout" has a similar name.  This option specifies the cut buffer to use.  The default is cut buffer 0.

DESCRIPTION

       The  xcutsel  program is used to copy the current selection into a cut buffer and to make a selection that contains the current contents of
       the cut buffer.	It acts as a bridge between applications that do not support selections and those that do.

       By default, xcutsel will use the selection named PRIMARY and the cut buffer CUT_BUFFER0.  Either or both of these can be overridden by com-
       mand line arguments or by resources.

       An  xcutsel window has the following buttons: When this button is pressed, xcutsel exits.  Any selections held by xcutsel are automatically
       released.  When this button is pressed, xcutsel copies the current selection into the cut buffer.  When this  button  is  pressed,  xcutsel
       converts the current contents of the cut buffer into the selection.

       The button labels reflect the selection and cutbuffer selected by command line options or through the resource database.

       When  the  "copy  0 to PRIMARY" button is activated, the button will remain inverted as long as xcutsel remains the owner of the selection.
       This serves to remind you which client owns the current selection.  Note that the value of the selection remains constant; if the cutbuffer
       is changed, you must again activate the copy button to retrieve the new value when desired.

X DEFAULTS

       This program accepts all of the standard X Toolkit resource names and classes as well as: This resource specifies the name of the selection
       to use.	The default is PRIMARY.  This resource specifies the number of the cut buffer to use.  The default is 0.

WIDGET NAMES

       The following instance names may be used when user configuration of the labels in them is desired: This is the "copy SELECTION  to  BUFFER"
       button.	This is the "copy BUFFER to SELECTION" button.	This is the "quit" button.

BUGS

       There is no way to change the name of the selection or the number of the cut buffer while the program is running.

SEE ALSO

       X(1X), xclipboard(1X), xterm(1X), text widget documentation, individual client documentation for how to make a selection.

AUTHOR

       Ralph R. Swick, DEC/MIT Project Athena

																       xcutsel(1X)
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