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Top Forums Shell Programming and Scripting Reading ALL BUT the first and last line of a huge file Post 302969946 by Scrutinizer on Wednesday 30th of March 2016 01:52:00 PM
Old 03-30-2016
Tested with a 2 GB file (excluding writing to a file which should be similar for all approaches):
Code:
$ time sed '1d;$d' greptestin1 > /dev/null

real	0m29.835s
user	0m29.186s
sys	0m0.591s
$ time awk 'NR>2{print p}{p=$0}' greptestin1 > /dev/null    # BSD awk

real	1m44.183s
user	1m43.627s
sys	0m0.481s
$ time mawk 'NR>2{print p}{p=$0}' greptestin1 > /dev/null

real	0m14.982s
user	0m14.463s
sys	0m0.498s
$ time gawk 'NR>2{print p}{p=$0}' greptestin1 > /dev/null

real	0m24.682s
user	0m24.210s
sys	0m0.414s
$ time gawk4 'NR>2{print p}{p=$0}' greptestin1 > /dev/null

real	0m27.621s
user	0m27.173s
sys	0m0.419s

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print(9E)							Driver Entry Points							 print(9E)

NAME
print - display a driver message on system console SYNOPSIS
#include <sys/types.h> #include <sys/errno.h> #include <sys/ddi.h> #include <sys/sunddi.h> int prefixprint(dev_t dev, char *str); INTERFACE LEVEL
Architecture independent level 1 (DDI/DKI). This entry point is required for block devices. PARAMETERS
dev Device number. str Pointer to a character string describing the problem. DESCRIPTION
The print() routine is called by the kernel when it has detected an exceptional condition (such as out of space) in the device. To display the message on the console, the driver should use the cmn_err(9F) kernel function. The driver should print the message along with any driver specific information. RETURN VALUES
The print() routine should return 0 for success, or the appropriate error number. The print routine can fail if the driver implemented a non-standard print() routine that attempted to perform error logging, but was unable to complete the logging for whatever reason. SEE ALSO
cmn_err(9F) Writing Device Drivers SunOS 5.10 15 Sep 1992 print(9E)
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