the spaceship operator, <=>, is a comparison function, for numeric data only. It compares elements in the input array, @unsorted. The output of the sort call is written to the array @sorted. If no comparison function statement was entered (a blank), then sort works on the @unsoted array as letters of the alphabet, not numbers.
$a and $b are individual elements in the unosrted array - in this case numbers
If element $a is equal to element $b, then it returns 0; if $a is less than $b it returns -1; if $a is greater it returns +1 .
So the general statement is:
Internally perl sort calls a standard C library function, qsort for doing the comparisons and reordering over and entire array -or at least it did years ago. qsort(3): sort array - Linux man page
These 3 Users Gave Thanks to jim mcnamara For This Post:
Hi Friends,
Can any of you explain me about the below line of code?
mn_code=`env|grep "..mn"|awk -F"=" '{print $2}'`
Im not able to understand, what exactly it is doing :confused:
Any help would be useful for me.
Lokesha (4 Replies)
Hi Everyone,
# cat a.txt
a;b;c;64O
a;b;c;d;ee;f
# cat a.pl
#!/usr/bin/perl
use strict;
use warnings;
my $tmp3 = ",,a,,b,,c,,d,,e,,f,,";
open(my $FA, "a.txt") or die "$!";
while(<$FA>) {
chomp;
my @tmp=split(/\;/, $_);
if ( ($tmp =~ m/^(64O)/i) || ($tmp... (3 Replies)
I am running a program written in perl script and it is stopped with "Out of memory!" error. This is very strange because at the time then the program is aborted, it only used 4GB RAM and there are still 30GB free physical memory left in the system. I check the perl script and found the program... (3 Replies)
I need to sort the following file by the rhdiskpower devices in the last column:
Total_MB Free_MB OS_MB Name Failgroup Library Label UDID Product Redund Path
1024 851 1024 OCRVOT1_0000 OCRVOT1_0000 System UNKNOWN ... (3 Replies)
Hi,
I have line in input file as below:
3G_CENTRAL;INDONESIA_(M)_TELKOMSEL;SPECIAL_WORLD_GRP_7_FA_2_TELKOMSEL
My expected output for line in the file must be :
"1-Radon1-cMOC_deg"|"LDIndex"|"3G_CENTRAL|INDONESIA_(M)_TELKOMSEL"|LAST|"SPECIAL_WORLD_GRP_7_FA_2_TELKOMSEL"
Can someone... (7 Replies)
I have seen something like this in a perl code:
$_ =~ s/__FD_PRN_/\\(/g
What does this "__FD_PRN_" means. I have searched google but was not able to find any info regarding this. Appreciate if some one can refer to a link for these characters. From comments/code it used to substitue "(" with... (3 Replies)
Hi All,
I have 2 pipe delimited files viz., file_old and file_new. I'm trying to compare these 2 files, and extract all the different rows between them into a new_file.
comm -3 < sort file_old < sort file_new > new_file
I am getting the below error:
-ksh: sort: cannot open
But if I do... (7 Replies)
Hello.
System : opensuse leap 42.3
I have a bash script that build a text file.
I would like the last command doing :
print_cmd -o page-left=43 -o page-right=22 -o page-top=28 -o page-bottom=43 -o font=LatinModernMono12:regular:9 some_file.txt
where :
print_cmd ::= some printing... (1 Reply)
Discussion started by: jcdole
1 Replies
LEARN ABOUT OSX
psort_r
PSORT(3) BSD Library Functions Manual PSORT(3)NAME
psort, psort_b, psort_r -- parallel sort functions
SYNOPSIS
#include <stdlib.h>
void
psort(void *base, size_t nel, size_t width, int (*compar)(const void *, const void *));
void
psort_b(void *base, size_t nel, size_t width, int (^compar)(const void *, const void *));
void
psort_r(void *base, size_t nel, size_t width, void *thunk, int (*compar)(void *, const void *, const void *));
DESCRIPTION
The psort(), psort_b(), and psort_r() functions are parallel sort routines that are drop-in compatible with the corresponding qsort() func-
tion (see qsort(3) for a description of the arguments). On multiprocessor machines, multiple threads may be created to simultaneously per-
form the sort calculations, resulting in an overall faster sort result. Overhead in managing the threads limits the maximum speed improve-
ment to somewhat less that the number of processors available. For example, on a 4-processor machine, a typical sort on a large array might
result in 3.2 times faster sorting than a regular qsort().
RESTRICTIONS
Because of the multi-threaded nature of the sort, the comparison function is expected to perform its own synchronization that might be
required for data physically outside the two objects passed to the comparison function. However, no synchronization is required for the two
object themselves, unless some third party is also accessing those objects.
Additional memory is temporary allocated to deal with the parallel nature of the computation.
Because of the overhead of maintaining multiple threads, the psort() family of routines may choose to just call qsort(3) when there is no
advantage to parallelizing (for example, when the number of objects in the array is too small, or only one processor is available).
Like qsort(3), the sort is not stable.
RETURN VALUES
The psort(), psort_b() and psort_r() functions return no value.
SEE ALSO qsort(3)Mac OS X Nov 25, 2008 Mac OS X