Adding one more small example here too. In awk, strings could be converted to numbers and numbers could be converted to strings, if the context of the awk program demands it. For example, If numeric values appear in string concatenation, they are converted to strings. Consider the following:
This prints the (numeric) value 27. The numeric values of the variables two and three are converted to strings and concatenated together. The resulting string is converted back to the number 23, to which 4 is then added. Also while taking 5th field of dfin BASH means to have the used file system percentage could be one more example for this too.
Thanks,
R. Singh
Last edited by RavinderSingh13; 05-26-2016 at 05:04 PM..
Hi,
I am facing one problem only with mv command not with cp command. I have a test program
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mount.h>
#include <fcntl.h>
#include <errno.h>
int sync_file(char *file)
{
FILE *fp=NULL;... (6 Replies)
Hello all,
Here is what my bash script does: sums number columns, saves the tot in new column, outputs if tot >= threshold val:
> cat getnon0file.sh
#!/bin/bash
this="getnon0file.sh"
USAGE=$this"
InFile="xyz.38"
Min="0.05"
#
awk '{sum=0; for(n=2; n<=NF; n++){sum+=$n};... (4 Replies)
What is the difference between (unix-system “which ) and which commands.
For example when I use the (unix-system “which visual_elite) command I get the following result:
/home/vhdl/edatools/mentor/visualelite/VisualElite-4.2.1/Linux2.4/bin/visual_elite
When I do the same on... (1 Reply)
Hey there,
I just stumbled upon a difference between using awk on the commandline and using it in a shellscript.
I have a variable, e.g.: PROG=vim
then i want to check if the package with this name is installed: TEMPVAL=$(dpkg -l | awk '{ if ($2 == "$PROG") print $2 }') (Im using... (10 Replies)
Hello,
I have two text files, each with a single column,
file 1:
124152970
123899868
123476854
54258288
123117283
file 2:
124152970
123899868
54258288
123117283
122108330 (5 Replies)
I have awk appearing to behave inconsistently. With the same variable it will give the message:
fatal: attempt to use array `X' in a scalar context
and, if I try to correct that, then:
fatal: attempt to use a scalar value as array
I'm using a three dimensional array. There seems to be a... (2 Replies)
so, im going over one of my scripts and trying to optimize it.
i have a code like this:
cksum sjreas.py | awk '{prinnt $1$2}'
This does what I need. However, i dont want to call the external command awk. so im doing this:
cksum sjreas.py | while OFS=' ' read v1 v2 ; do printf... (4 Replies)
In the awk I am trying to subtract the difference $3-$2 of each matching $4 before the first _ (underscore) and print that value in $13.
I think the awk will do that, but added comments. What I am not sure off is how to add a line or lines that will add sum each matching $13 value and put it in... (2 Replies)
Discussion started by: cmccabe
2 Replies
LEARN ABOUT FREEBSD
stdbuf
STDBUF(1) BSD General Commands Manual STDBUF(1)NAME
stdbuf -- change standard streams initial buffering
SYNOPSIS
stdbuf [-e bufdef] [-i bufdef] [-o bufdef] [command [...]]
DESCRIPTION
stdbuf is used to change the initial buffering of standard input, standard output and/or standard error streams for command. It relies on
libstdbuf(3) which is loaded and configured by stdbuf through environment variables.
The options are as follows:
-e bufdef
Set initial buffering of the standard error stream for command as defined by bufdef (see BUFFER DEFINITION).
-i bufdef
Set initial buffering of the standard input stream for command as defined by bufdef (see BUFFER DEFINITION).
-o bufdef
Set initial buffering of the standard output stream for command as defined by bufdef (see BUFFER DEFINITION).
BUFFER DEFINITION
Buffer definition is the same as in libstdbuf(3):
"0" unbuffered
"L" line buffered
"B" fully buffered with the default buffer size
size fully buffered with a buffer of size bytes (suffixes 'k', 'M' and 'G' are accepted)
EXAMPLES
In the following example, the stdout stream of the awk(1) command will be fully buffered by default because it does not refer to a terminal.
stdbuf is used to force it to be line-buffered so vmstat(8)'s output will not stall until the full buffer fills.
# vmstat 1 | stdbuf -o L awk '$2 > 1 || $3 > 1' | cat -n
SEE ALSO libstdbuf(3), setvbuf(3)HISTORY
The stdbuf utility first appeared in FreeBSD 8.4.
AUTHORS
The original idea of the stdbuf command comes from Padraig Brady who implemented it in the GNU coreutils. Jeremie Le Hen implemented it on
FreeBSD.
BSD April 28, 2012 BSD