Sponsored Content
Top Forums Shell Programming and Scripting Explanation of print statement - awk Post 302764773 by Don Cragun on Friday 1st of February 2013 01:25:50 AM
Old 02-01-2013
Quote:
Originally Posted by Corona688
I can see why you're puzzled, that took some thought.

Nothing at all is assigned to X. It's printing a newline. print "" would have the same effect, but they saved one character by using a blank variable. Just print all by itself with no parameters would print the entire line, not what you want.

The printf statements do not print newlines, those must be explicit when using printf. So it prints a bunch of things into one long line, then uses print "" to finish off the line.

Are you sure that's OFS,$i and not OFS $i ? Two things into a single %s is a syntax error as far as I know.
It isn't a syntax error, but it isn't common. The awk printf command:
Code:
printf "%s" OFS,$i

uses the concatenation of "%s" and OFS as a format string; together they print the contents of the ith input field followed by the output field separator. If there is a bug here, it is that there is an extraneous trailing field separator printed at the end of each output line before the <newline> added by the print x command.
These 2 Users Gave Thanks to Don Cragun For This Post:
 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

AWK explanation

Hi, Could anyone please explain why we have arr=1 - what does this statement do? awk -F\; 'FNR==NR{arr=1;next};$3 in arr' core.txt gmrd.txt Any help appreciated (2 Replies)
Discussion started by: penfold
2 Replies

2. Shell Programming and Scripting

Print to 2 files in awk if statement

Hi all, I have some code like this awk -F, '{ if ($1==3) print $2 > "output_file" print "1" > "new_file" }' "input_file" When I check output_file this has the correct values in it. However the new_file has 1 in it for every line in the input_file. If the input file has 20 lins then... (2 Replies)
Discussion started by: Donkey25
2 Replies

3. Shell Programming and Scripting

Explanation for printf string in awk

hi all can any one help me to understand this bdf -t vfxs | awk '/\//{printf("%-30s%-10s%-10s%-10s%-5s%-10s\n",$1,$2,$3,$4,$5,$6)}' i want to understand the numbers %-30S% (4 Replies)
Discussion started by: maxim42
4 Replies

4. Shell Programming and Scripting

awk explanation

Hello, I have recently come across this awk program. Can some one shed some light on what is taking place. awk '{!a++}END{for(i in a) if ( a >10 ) print a,i }' $FILE Best Regards, jaysunn (1 Reply)
Discussion started by: jaysunn
1 Replies

5. Shell Programming and Scripting

Help with explanation of awk parameters

Hello, Would someone be able to tell me exactly how this command works please? awk '!x++' As usual any help much appreciated (8 Replies)
Discussion started by: Grueben
8 Replies

6. Shell Programming and Scripting

Sysdate inside awk print statement

Hi, I am using awk statement to extract data from a file and write a new file with certain columns rearranged and few hard coded values added to new file. Now i need to add a column with sysdate. can i do that inside the awk print statement? Now: nawk ' /^3/ BEGIN {FS=","}... (2 Replies)
Discussion started by: selvankj
2 Replies

7. Shell Programming and Scripting

use awk print statement for two files

Hello, is there a way to use the awk print statement on two files at once? I would like to take two columns from one file, and one column from another file and print them as consecutive columns to a third file. Seems simple...as in: file 1 1 a 2 b 3 c 4 d 5 e file 2 1 t 2 u... (3 Replies)
Discussion started by: HugoHuhn
3 Replies

8. Shell Programming and Scripting

Awk find in columns with "if then" statement and print results

I have a file1.txt file1.txt F-120009210","Felix","U-M-F-F-F-","white","yes","no","U-M-F-F-F-","Bristol","RI","true" F-120009213","Fluffy","U-F-","white","yes","no","M-F-","Warwick","RI","true" U-120009217","Lity","U-M-","grey","yes","yes","","Fall River","MA","true"... (4 Replies)
Discussion started by: charles33
4 Replies

9. UNIX for Dummies Questions & Answers

If statement explanation

Could anyone please advise what the in the following if statement means? if ; then Thank you. (2 Replies)
Discussion started by: jimbojames
2 Replies

10. Shell Programming and Scripting

Convert Update statement into Insert statement in UNIX using awk, sed....

Hi folks, I have a scenario to convert the update statements into insert statements using shell script (awk, sed...) or in database using regex. I have a bunch of update statements with all columns in a file which I need to convert into insert statements. UPDATE TABLE_A SET COL1=1 WHERE... (0 Replies)
Discussion started by: dev123
0 Replies
ICON(1) 						      General Commands Manual							   ICON(1)

NAME
icon - interpret or compile Icon programs SYNOPSIS
icont [ option ... ] file ... [ -x arg ... ] iconc [ option ... ] file ... [ -x arg ... ] DESCRIPTION
icont and iconc each convert an Icon source program into executable form. icont translates quickly and provides interpretive execution. iconc takes longer to compile but produces programs that execute faster. icont and iconc for the most part can be used interchangeably. This manual page describes both icont and iconc. Where there there are differences in usage between icont and iconc, these are noted. File Names: Files whose names end in .icn are assumed to be Icon source files. The .icn suffix may be omitted; if it is not present, it is supplied. The character - can be used to indicate an Icon source file given in standard input. Several source files can be given on the same command line; if so, they are combined to produce a single program. The name of the executable file is the base name of the first input file, formed by deleting the suffix, if present. stdin is used for source programs given in standard input. Processing: As noted in the synopsis above, icont and iconc accept options followed by file names, optionally followed by -x and arguments. If -x is given, the program is executed automatically and any following arguments are passed to it. icont: The processing performed by icont consists of two phases: translation and linking. During translation, each Icon source file is translated into an intermediate language called ucode. Two ucode files are produced for each source file, with base names from the source file and suffixes .u1 and .u2. During linking, the one or more pairs of ucode files are combined to produce a single icode file. The ucode files are deleted after the icode file is created. Processing by icont can be terminated after translation by the -c option. In this case, the ucode files are not deleted. The names of .u1 files from previous translations can be given on the icont command line. These files and the corresponding .u2 files are included in the linking phase after the translation of any source files. The suffix .u can be used in place of .u1; in this case the 1 is supplied auto- matically. Ucode files that are explicitly named are not deleted. iconc: The processing performed by iconc consists of two phases: code generation and compilation and linking. The code generation phase produces C code, consisting of a .c and a .h file, with the base name of the first source file. These files are then compiled and linked to produce an executable binary file. The C files normally are deleted after compilation and linking. Processing by iconc can be terminated after code generation by the -c option. In this case, the C files are not deleted. OPTIONS
The following options are recognized by icont and iconc: -c Stop after producing intermediate files and do not delete them. -e file Redirect standard error output to file. -f s Enable full string invocation. -o name Name the output file name. -s Suppress informative messages. Normally, both informative messages and error messages are sent to standard error output. -t Arrange for &trace to have an initial value of -1 when the program is executed and for iconc enable debugging features. -u Issue warning messages for undeclared identifiers in the program. -v i Set verbosity level of informative messages to i -E Direct the results of preprocessing to standard output and inhibit further processing. The following additional options are recognized by iconc: -f string Enable features as indicated by the letters in string: a all, equivalent to delns d enable debugging features: display(), name(), variable(), error trace back, and the effect of -f n (see below) e enable error conversion l enable large-integer arithmetic n produce code that keeps track of line numbers and file names in the source code s enable full string invocation -n string Disable specific optimizations. These are indicated by the letters in string: a all, equivalent to cest c control flow optimizations other than switch statement optimizations e expand operations in-line when reasonable (keywords are always put in-line) s optimize switch statements associated with operation invocations t type inference -p arg Pass arg on to the C compiler used by iconc -r path Use the run-time system at path, which must end with a slash. -C prg Have iconc use the C compiler given by prg ENVIRONMENT VARIABLES
When an Icon program is executed, several environment variables are examined to determine certain execution parameters. Values in paren- theses are the default values. BLKSIZE (500000) The initial size of the allocated block region, in bytes. COEXPSIZE (2000) The size, in words, of each co-expression block. DBLIST The location of data bases for iconc to search before the standard one. The value of DBLIST should be a blank-separated string of the form p1 p2 ... pn where the pi name directories. ICONCORE If set, a core dump is produced for error termination. ICONX The location of iconx, the executor for icode files, is built into an icode file when it is produced. This location can be overridden by setting the environment variable ICONX. If ICONX is set, its value is used in place of the location built into the icode file. IPATH The location of ucode files specified in link declarations for icont. IPATH is a blank-separated list of directories. The current directory is always searched first, regardless of the value of IPATH. LPATH The location of source files specified in preprocessor $include directives and in link declarations for iconc. LPATH is otherwise sim- ilar to IPATH. MSTKSIZE (10000) The size, in words, of the main interpreter stack for icont. NOERRBUF By default, &errout is buffered. If this variable is set, &errout is not buffered. QLSIZE (5000) The size, in bytes, of the region used for pointers to strings during garbage collection. STRSIZE (500000) The initial size of the string space, in bytes. TRACE The initial value of &trace. If this variable has a value, it overrides the translation-time -t option. FILES
icont Icon translator iconc Icon compiler iconx Icon executor SEE ALSO
The Icon Programming Language, Ralph E. Griswold and Madge T. Griswold, Prentice-Hall Inc., Englewood Cliffs, New Jersey, Second Edition, 1990. Version 9.1 of Icon, Ralph E. Griswold, Clinton L. Jeffery, and Gregg M. Townsend, IPD267, Department of Computer Science, The University of Arizona, 1995. Version 9 of the Icon Compiler, Ralph E. Griswold, IPD237, Department of Computer Science, The University of Arizona, 1995. icon_vt(1) LIMITATIONS AND BUGS
The icode files for the interpreter do not stand alone; the Icon run-time system (iconx) must be present. Stack overflow is checked using a heuristic that is not always effective. 1 November 1995 IPD244b ICON(1)
All times are GMT -4. The time now is 09:03 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy