how this works? Post: 302232235

10 More Discussions You Might Find Interesting

1. Linux

How does NORET_TYPE works ?

Hi, I was looking at the panic() code in linux kernel which is defined as: 51 /** 52 * panic - halt the system 53 * @fmt: The text string to print 54 * 55 * Display a message, then perform cleanups. 56 * 57 * This function never returns. 58 */ 59 60 NORET_TYPE void panic(const char *...

2. Shell Programming and Scripting

Help it works but its to SLOW

I am a novice at shell scripting. I have managed to cobble together a script that does exactly what I need it to do. However I am gathering information from 700+ devices. This script takes hours to complete the task. Is there a better way of doing it than what I have listed here? This script...

3. UNIX for Dummies Questions & Answers

How ls | wc -l works?

ls displays files in tabbed output. Say a directory contains 3 files. ls will list all 3 in one line. So, I expect ls | wc -l to give 1, but it counts the nr of files and gives 3. Can someone explain how this works?

4. Shell Programming and Scripting

Still trying to get a grep -c that works

I am trying to get a count of each line sub runit2 { my ($file1a, $file2a) = @_; my $file1_vala = $file1a->get; my $file2_vala = $file2a->get; open (FILE1a, "$file1_vala") or die; open (FILE2a, "$file2_vala") or die; chomp(my @strings = <FILE2a>); while (1) { foreach $pattern...

5. UNIX for Dummies Questions & Answers

>./a.pl works, >a.pl - does not

When I try to execute script, I get message: >aa.pl zsh: command not found: aa.pl but >./aa.pl works OK. What to change in environment to force the former way to work? Thank you, Alex Z

6. UNIX for Advanced & Expert Users

How this works?

I have a program............ #include<stdio.h> #include<unistd.h> main() { if(fork == 0) { printf("Hi every body:p!!!!!!!!!!"); } } This program works with out any error. here fork is not a system call. It just act as a variable.But how it works without declaring it? What data type it...

7. Shell Programming and Scripting

[ask]how does sed -e 's/<[^>]*>//g' works?

I found this command, sed -e 's/<*>//g', will return the content of a line with pattern something like this, <tag1>content</tag1>.. How does this works? What does sed -e 's/<*>//g' actually do? What if I wanted to get content of a line with pattern something like this, content? thanks..

8. Shell Programming and Scripting

How does a if works in shell

Hi, I need to compare and get an output for values greater than "X10" (values contain both characters and numbers) using if loop... FOR EG: I want to export values greater than X10, i.e., in-case if the value is X11 and greater than the "if" part to be executed if the value is X9 and...

9. UNIX for Dummies Questions & Answers

How zcat works?

Hi, just i would like to know, how will be the response if you try to read a 40GB compressed file using zcat. a)Uncompress the 40GB file and have it in the disk. use cat to view the steps. b)Use zcat directly to view the compressed file? What are the steps being occurred in step (b)? Where...

10. Shell Programming and Scripting

How mailx -r works?

I'm using Sun Solaris. I used mailx -r "MyEmailId" -s "sub" "toEmailID" from my unix id and it worked. But when i run the same script from other's unix id it works as well. mean any one in my environment can mail to other's email without my knowledge. My questions are How it works and why it...

LEARN ABOUT BSD

xargs

XARGS(1)						      General Commands Manual							  XARGS(1)

NAME

       xargs - construct argument list(s) and execute utility

SYNOPSIS

       xargs [ -t ][[ -x ] -n number ][ -s size ][ utility [ arguments...  ]]

DESCRIPTION

       The  xargs utility reads space, tab, newline and end-of-file delimited arguments from the standard input and executes the specified utility
       with them as arguments.

       The utility and any arguments specified on the command line are given to the utility upon each invocation, followed by some number  of  the
       arguments read from standard input.  The utility is repeatedly executed until standard input is exhausted.

       Spaces,	tabs  and  newlines  may  be embedded in arguments using single (`` ' '') or double (``"'') quotes or backslashes (``'').  Single
       quotes escape all non-single quote characters, excluding newlines, up to the matching single quote.  Double quotes  escape  all	non-double
       quote characters, excluding newlines, up to the matching double quote.  Any single character, including newlines, may be escaped by a back-
       slash.

       The options are as follows:

       -n number Set the maximum number of arguments taken from standard input for each invocation of the utility.  An invocation of utility  will
		 use less than number standard input arguments if the number of bytes accumulated (see the s option) exceeds the specified size or
		 there are fewer than number arguments remaining for the last invocation of utility.  The current  default  value  for	number	is
		 5000.

       -s size	 Set  the  maximum number of bytes for the command line length provided to utility.  The sum of the length of the utility name and
		 the arguments passed to utility (including /dev/null terminators) will be less than or equal to this number.  The current default
		 value for size is ARG_MAX - 2048.

       -t	 Echo the command to be executed to standard error immediately before it is executed.

       -x	 Force	xargs  to  terminate  immediately if a command line containing number arguments will not fit in the specified (or default)
		 command line length.

       If no utility is specified, echo(1) is used.

       Undefined behavior may occur if utility reads from the standard input.

       The xargs utility exits immediately (without processing any further input) if a	command  line  cannot  be  assembled,  utility	cannot	be
       invoked, an invocation of the utility is terminated by a signal or an invocation of the utility exits with a value of 255.

       The xargs utility exits with a value of 0 if no error occurs.  If utility cannot be invoked, xargs exits with a value of 127.  If any other
       error occurs, xargs exits with a value of 1.

SEE ALSO

       echo(1), find(1)

STANDARDS

       The xargs utility is expected to be IEEE Std 1003.2("POSIX") compliant.

								   June 6, 1993 							  XARGS(1)

10 More Discussions You Might Find Interesting

1. Linux

How does NORET_TYPE works ?

Discussion started by: amit4g

2. Shell Programming and Scripting

Help it works but its to SLOW

Discussion started by: Garlandxj

3. UNIX for Dummies Questions & Answers

How ls | wc -l works?

Discussion started by: krishmaths

4. Shell Programming and Scripting

Still trying to get a grep -c that works

Discussion started by: popeye