Sponsored Content
Full Discussion: understanding {%/*}/
Top Forums UNIX for Dummies Questions & Answers understanding {%/*}/ Post 302445386 by vemana on Sunday 15th of August 2010 11:27:20 PM
Old 08-16-2010
understanding {%/*}/

Hi Gurus:
I am trying to understand the following line of code.I did enough of googling to understand but no luck.Please help me understand the follow chunk of code:

X=$0
MOD=${X%/*}/env.ksh

X is the current script from which I am trying to execute.

Say if X=test.ksh

$MOD is echoing : "test.ksh/env.ksh"

What I am trying to understand is,What exactly is {X%/*} doing.

Thanks in advance

Last edited by Scott; 08-16-2010 at 02:06 AM.. Reason: Moved from AIX forum
 

9 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

need help understanding mv

I just started shell coding and I'm a bit confused on how 'mv' works can someone explain to me how it works and if i did this correctly. Thanks. echo "Enter Name of the first file:" read file1 #echo $file1 if ; then echo "Sorry, file does not exist." exit 1 ... (16 Replies)
Discussion started by: taiL
16 Replies

2. Shell Programming and Scripting

Need help for understanding of script

# sub: find block (in cols), return line-numbers (begin-end) or 0 if notfound sub findb{ my ($exp1,$col1,$exp2,$col2)= @_; # $exp = expression to find, $col - column to search in my $cnt=0; my ($val1,$val2); my ($beg,$end); for($cnt=1;$cnt<=65536;$cnt++){ $val1 =... (3 Replies)
Discussion started by: suvenduperl
3 Replies

3. Solaris

Understanding 'du' command

Hi I have a questions related 2 commands : 'du' and 'ls'. Why is the difference between output of 'du' and 'ls' cmd's ? Command 'du' : ------------------ jakubn@server1 /home/jakubn $ du -s * 4 engine.ksh 1331 scripts 'du -s *' ---> shows block count size on disk (512 Bytes... (5 Replies)
Discussion started by: presul
5 Replies

4. Shell Programming and Scripting

Understanding <<EOF

Hi all I stuck with a problem. I want to understand the execution of the below code. Can any one please help me `sqlplus username/passwd@DB << EOF set serveroutput on declare begin sql_query; end; / commit / quit EOF` My ques is why do we use EOF and how does it help. (4 Replies)
Discussion started by: parthmittal2007
4 Replies

5. Shell Programming and Scripting

Understanding a regex

Hi, Please help me to understand the bold segments in the below regex. Both are of same type whose meaning I am looking for. find . \( -iregex './\{6,10\}./src' \) -type d -maxdepth 2 Output: ./20111210.0/src In continuation to above: sed -e 's|./\(*.\{1,3\}\).*|\1|g' Output: ... (4 Replies)
Discussion started by: vibhor_agarwali
4 Replies

6. Shell Programming and Scripting

Help understanding the script

Hi Guys, I am new to scripting , I am trying to rebuild a script based on an old script. Can someone help me figure out what the script is doing? This is only a part of the script. I am looking to interpret these two points in the scripts:- 1) test=`echo $?` while I do not... (3 Replies)
Discussion started by: rajsan
3 Replies

7. Shell Programming and Scripting

Help with understanding of alias

Hi, I saw the following explanation about alias in bash from gnu website, but I didn't get the meaning: Bash always reads at least one complete line of input before executing any of the commands on that line. Aliases are expanded when a command is read, not when it is executed. Therefore, an... (3 Replies)
Discussion started by: Roy987
3 Replies

8. UNIX for Dummies Questions & Answers

Understanding lseek

I tried to use lseek system call to determine the number of bytes in a file. To do so, I used open system call with O_APPEND flag to open a file. As lseek returns the current offset so I called lseek for opened file with offset as zero and whence as SEEK_CUR. So I guess it must return the number of... (3 Replies)
Discussion started by: Deepak Raj
3 Replies

9. Shell Programming and Scripting

Need your help in understanding this

Hi, I found this in a script and I would like to know how this works Code is here: # var1=PART1_PART2 # var2=${var1##*_} # echo $var2 PART2 I'm wondering how ##* makes the Shell to understand to pick up the last value from the given. (2 Replies)
Discussion started by: sathyaonnuix
2 Replies
echo(1B)					     SunOS/BSD Compatibility Package Commands						  echo(1B)

NAME
echo - echo arguments to standard output SYNOPSIS
/usr/ucb/echo [-n] [argument] DESCRIPTION
echo writes its arguments, separated by BLANKs and terminated by a NEWLINE, to the standard output. echo is useful for producing diagnostics in command files and for sending known data into a pipe, and for displaying the contents of envi- ronment variables. For example, you can use echo to determine how many subdirectories below the root directory (/) is your current directory, as follows: o echo your current-working-directory's full pathname o pipe the output through tr to translate the path's embedded slash-characters into space-characters o pipe that output through wc -w for a count of the names in your path. example% /usr/bin/echo "echo $PWD | tr '/' ' ' | wc -w" See tr(1) and wc(1) for their functionality. The shells csh(1), ksh(1), and sh(1), each have an echo built-in command, which, by default, will have precedence, and will be invoked if the user calls echo without a full pathname. /usr/ucb/echo and csh's echo() have an -n option, but do not understand back-slashed escape characters. sh's echo(), ksh's echo(), and /usr/bin/echo, on the other hand, understand the black-slashed escape characters, and ksh's echo() also understands a as the audible bell character; however, these commands do not have an -n option. OPTIONS
-n Do not add the NEWLINE to the output. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Availability |SUNWscpu | +-----------------------------+-----------------------------+ SEE ALSO
csh(1), echo(1), ksh(1), sh(1), tr(1), wc(1), attributes(5) NOTES
The -n option is a transition aid for BSD applications, and may not be supported in future releases. SunOS 5.11 3 Aug 1994 echo(1B)
All times are GMT -4. The time now is 03:16 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy