Login or Register to Ask a Question and Join Our Community

Sponsored Content
Full Discussion: Bash - concatenate string - strange variable scoping
Top Forums Shell Programming and Scripting Bash - concatenate string - strange variable scoping Post 302980736 by Don Cragun on Thursday 1st of September 2016 04:43:55 PM
Old 09-01-2016
In POSIX, it is unspecified whether or not the last stage of a pipeline is run in the current shell execution environment. (In ksh it is and the script in post #1 would work without change; in bash it is not and the value of a variable set in the last stage of the pipeline disappears when the pipeline completes execution.)

With any POSIX conforming shell, you could modify disedorgue's suggestion to:
Code:
runCmd="docker run -e \"IMAGE_NAME=$IMAGE_NAME\" "
while read line; do
   envCmd="-e \"${line}\" "
   runCmd=$runCmd$envCmd
   echo $runCmd # here concatenation works fine
done <<EOF
$(env | grep "$ENV_SUFFIX")
EOF
echo $runCmd # and concatenation works here too

and get what you want.
 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

ksh/Linux: Variable scoping issue? Pl. help!

user_account() { set -x nodename=$1 # set userid to user0 userid="user0" echo outside:pid $$ cat $MY_DIR/user_accounts | while read line do # line="node1 user1" echo inside do: pid $$ line:$line userid:$userid poss_node=`echo $line |awk '{print $1}'`... (2 Replies)
Discussion started by: jasmeet100
2 Replies

2. Shell Programming and Scripting

How to concatenate a string and a variable

I need a way to build variable in this manner: variable_$i Inside a for loop i need to create it. where i goes from 1 to 30.. and then i need to print them on screen with echo $variable_$i which is the best way to do this? (6 Replies)
Discussion started by: sreedivia
6 Replies

3. Shell Programming and Scripting

Bash string variable manipulation

In a bash script I've set a variable that is the directory name of where an executable lives. the_dir=`dirname $which myscript` which equates to something like "/path/to/dir/bin" I need to cut that down to remove the "bin" so I now have "/path/to/dir/". This sounds easy but as a... (2 Replies)
Discussion started by: Witty
2 Replies

4. UNIX for Dummies Questions & Answers

Concatenate a string to a variable

Hello All, How to concatenate a string to a variable in a script I'm having a file which is consisting of data and i need to extract the first line of the file and append it to a string. /tmp/samp.list containg 60000 I like to concatenate it with a string (SS_) grep -w SS_$(head -1... (1 Reply)
Discussion started by: nkamalkishore
1 Replies

5. Shell Programming and Scripting

Shell variable scoping

This may be a stupid question, but was wondering if it is possible to make a variable local to a particular script and invisible to an external script that may source the script where it is defined? Thanks as always (2 Replies)
Discussion started by: stevensw
2 Replies

6. Shell Programming and Scripting

Bash assign string to variable

Hi ,I am trying to assign string to variable ,but it doesn't work Also could you show me different ways to use grep,(I am trying to get the first,second and first column form file,and I am counting the chars) let name=`grep "$id" product | cut -c6-20` (25 Replies)
Discussion started by: lio123
25 Replies

7. UNIX for Dummies Questions & Answers

bash variable string declaration

Hello, Why is this not working in a script? files="test.fsa" echo $files for file in $files do if then echo "$file does not exist." fi run a command done I get an error saying (3 Replies)
Discussion started by: verse123
3 Replies

8. Shell Programming and Scripting

Search for string in a file, extract two another strings and concatenate to a variable

I have a file with <suit:run date="Trump Tue 06/19/2012 11:41 AM EDT" machine="garg-ln" build="19921" level="beta" release="6.1.5" os="Linux"> Need to find word "build" then extract build number, which is 19921 also release number, which is 6.1.5 then concatenate them to one variable as... (6 Replies)
Discussion started by: garg
6 Replies

9. Shell Programming and Scripting

bash: using a string variable in grep

Hi, I've been stuck for several days on this. Using grep on a command line, I can use quotes, eg... grep 'pattern of several words' filename I want to do this in my bash script. In my script I have captured the several command line arguments (eg arg1 arg2) into a variable: variable=$@ I... (2 Replies)
Discussion started by: adrian777uk
2 Replies

10. Shell Programming and Scripting

Passing string as variable(s) in bash

I'm trying to write a basic bash script that takes input you give (what directory, if any, what name, if any ....) and passes the information to find. I'm trying to just create a string with all variables and then pass it to find. So far I have this extremely simple: #!/bin/bash -f ... (2 Replies)
Discussion started by: Starting_Leaf
2 Replies

LEARN ABOUT CENTOS

glbindprogrampipeline

GLBINDPROGRAMPIPELIN(3G)					   OpenGL Manual					  GLBINDPROGRAMPIPELIN(3G)

NAME

       glBindProgramPipeline - bind a program pipeline to the current context

C SPECIFICATION

       void glBindProgramPipeline(GLuint pipeline);

PARAMETERS

       pipeline
	   Specifies the name of the pipeline object to bind to the context.

DESCRIPTION

       glBindProgramPipeline binds a program pipeline object to the current context.  pipeline must be a name previously returned from a call to
       glGenProgramPipelines(). If no program pipeline exists with name pipeline then a new pipeline object is created with that name and
       initialized to the default state vector.

       When a program pipeline object is bound using glBindProgramPipeline, any previous binding is broken and is replaced with a binding to the
       specified pipeline object. If pipeline is zero, the previous binding is broken and is not replaced, leaving no pipeline object bound. If no
       current program object has been established by glUseProgram(), the program objects used for each stage and for uniform updates are taken
       from the bound program pipeline object, if any. If there is a current program object established by glUseProgram(), the bound program
       pipeline object has no effect on rendering or uniform updates. When a bound program pipeline object is used for rendering, individual
       shader executables are taken from its program objects.

ERRORS

       GL_INVALID_OPERATION is generated if pipeline is not zero or a name previously returned from a call to glGenProgramPipelines() or if such a
       name has been deleted by a call to glDeleteProgramPipelines().

SEE ALSO

       glCreateShader(), glCreateProgram(), glCompileShader(), glLinkProgram(), glGenProgramPipelines(), glDeleteProgramPipelines(),
       glIsProgramPipeline()

COPYRIGHT

       Copyright (C) 2010 Khronos Group. This material may be distributed subject to the terms and conditions set forth in the Open Publication
       License, v 1.0, 8 June 1999.  http://opencontent.org/openpub/.

AUTHORS

       opengl.org

opengl.org							    06/10/2014						  GLBINDPROGRAMPIPELIN(3G)
All times are GMT -4. The time now is 11:55 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy