I have been trying to get variable within variable expansion to work but have not been able to succeed. It seems that the two suggestions I am seeing are using 'eval' and using the built in bash capability of "${!test}". Here is a snippet of what I"m trying to accomplish:
This would be used as:
And ideally receive:
Can anyone shed some light on what I am doing wrong here? I appreciate any guidance.
We have a script that runs in ksh on HP-UX 11.11. It takes three arguments. The last argument can be a filename or wildcard character. For example:
script -s hello -t goodbye '*.d*'
In a case such as this, I would wrap single quotes around the final argument because I dont want the shell to... (4 Replies)
#!/usr/bin/bash
if
then
echo "Not valid arguments entered. Just username should be entered."
else
USER_NAME=$1
FILE_NAME=$USER_NAME.info
UNN=STUDIN\\\\$1
echo $UNN
last STUDIN\\\\$1
last UNN
If I type `last STUDIN\\eip060` it works but if I try to expand it with variable it is... (5 Replies)
Hello -
I have a bash script which does some logging, and I'd like to include the line number of the echo statement that pipes into $LOGGER:
MYPID=$$
MYNAME=`basename $0`
LOGGER="/usr/bin/logger -t $MYNAME($LINENO) -p daemon.error"
...
echo 'this is an entry into the log file' | $LOGGER
... (3 Replies)
I'm in the habit of using the following type of loop structure:
for num in `seq $1 $2`
do
command
doneWhile `seq $1 $2` is not exactly a huge resource hog, I would like to learn a better way. It seems that brace expansion is a good way to go:
for num in {3..10}The problem, though, is... (2 Replies)
i write a batch file , here is the content.
dirname='date +%Y-%m-%d'
mkdir dirname
but it doen's work, it just create a folder named date and +%Y-%m-%d.
i have tried run the command seperately in the bash prompt. after the first
sentence executed , i use $dirname to watch the value of... (4 Replies)
The objective of the code below is to create sed script to be later executed. However, it bonks because $ARCHIVENAME expands to a directory specification so the forward slashes cause problems. I can think of a few solutions that would involve redesigning the process, but I'm hoping there might be... (4 Replies)
Hi forum,
in my bash script I've many lines executing commands with redirection to log files.
...
xyz_cmd 2>&1 > $BASENAME.$LINENO
The trailing part of these lines doesn't look nice and I like to put it into a variable.
The (not working) idea is something like that
... (3 Replies)
So, I was bored on the train today, and was thinking of ways to loop through elements of an array. I came up with the following simple script, but it doesn't work as brace expansion doesn't seem to work with variables. Is there something I'm missing, or does the shell just not work like this?
... (4 Replies)
Hello,
I have one variable coming from one file:
abc=$xyz/filename.txt where $xyz is defined in .profile file as say, /usr/dev/src
i am passing abc variable to one perl script as input parameter.
perl 123.pl -s $abc
But inside the perl script execution, the variable $abc is just... (1 Reply)
Hello.
The file /etc/fstab contains
UUID=957c3295-9944-1593-82e2-2b90dede4312 / ext4 noatime,discard,acl,user_xattr 1 1
I fill a variable
SOME_LINE=$( cat /etc/fstab | grep \/\..*ext4 | grep noatime,discard )echo $SOME_LINE... (3 Replies)
Discussion started by: jcdole
3 Replies
LEARN ABOUT OPENDARWIN
printenv
PRINTENV(1) BSD General Commands Manual PRINTENV(1)NAME
printenv, env -- print out the environment, set and print environment
SYNOPSIS
printenv [name]
env [-i] [name=value ...] [utility [argument ...]]
DESCRIPTION
The printenv utility prints out the names and values of the variables in the environment, with one name/value pair per line. If name is
specified, only its value is printed.
Some shells may provide a builtin printenv command which is similar or identical to this utility. Consult the builtin(1) manual page.
The env utility executes utility after modifying the environment as specified on the command line. The option name=value specifies an envi-
ronment variable, name, with a value of value.
The options are as follows:
-i Execute the utility with only those environment values specified. The environment inherited by env is ignored completely.
If no utility is specified, env prints out the names and values of the variables in the environment, with one name/value pair per line.
The env utility is sometimes useful with the ``#!'' construct (see execve(2)). The only difference between ``#!/usr/local/bin/foo'' and
``#!/usr/bin/env /usr/local/bin/foo'' is that the latter works even if /usr/local/bin/foo is itself interpreted. Using env this way also
allows one to reference foo without the path, as well as set up the environment as desired.
ENVIRONMENT
The env utility uses the PATH environment variable is used to locate the requested utility if the name contains no '/' characters.
DIAGNOSTICS
The printenv utility exits 0 on success, and >0 if an error occurs.
The env utility exits 0 on success, and >0 if an error occurs. An exit status of 126 indicates utility was found, but could not be executed.
An exit status of 127 indicates utility could not be found.
COMPATIBILITY
The env utility accepts the - option as a synonym for -i.
SEE ALSO csh(1), sh(1), execvp(3), environ(7)STANDARDS
The env utility conforms to IEEE Std 1003.1-2001 (``POSIX.1'').
HISTORY
The printenv command appeared in 3.0BSD.
BUGS
The env utility doesn't handle utility arguments with equal (``='') signs in their names, for obvious reasons.
BSD June 6, 1993 BSD