This is because commands within a pipeline are run in subshells so the read statement is setting the variables is a subshell which has not impact on the main shell.
You can achieve what you want using process substitution like this:
Edit:
Also in bash 4.* and later you can use a shell option to run the last pipeline command in the current shell.
Note this only work for shells without job control, so in an interactive shell (as opposed to a script) you will also need turn off job control (set +m).
Quote:
lastpipe
If set, and job control is not active, the shell runs the last command of a pipeline
not executed in the background in the current shell environment.
Last edited by Chubler_XL; 01-30-2020 at 10:25 PM..
These 2 Users Gave Thanks to Chubler_XL For This Post:
Hi :)
The next script campares two files File1-Line1 vs File2-Line1, File1-Line1 vs File2-Line2... only if line contains "AS-", if LineX is not in File2 writes in aux, but "valor" is allways=1 never changes! :confused: What is wrong?
valor changes to 0 before break, after brake is again 1
... (3 Replies)
How...
can I read input by a user character by cahracter. And assign each character from the string to a variable?
Any help would be greatly appreciated!
Thank you! (1 Reply)
Hi
I am trying to write a function that needs to be able to assign the last run shell command to a variable. The actual command string itself not the exit code of the command.
I am using the bash command recall ability to do this as follows:
alias pb='ps | grep ash' ... (3 Replies)
i have a file in this format
curyymm PRVYYMM CDDMmmYY bddMmmyy eddMmmyy
--------- ------- ------------ ---------- -----------
0906 0905 09Jun09 01Jun09 30Jun09
----------- --------- ------------ ------------ -----------
i need to read the... (5 Replies)
I have a csv file with the values seperated by commas.I want to extract these values one by one and assign to a variable using shell script.Any ideas or code? (11 Replies)
Hi all,
I want write a csh script which must be able:
1.read a file
2.assign value in file as variable
and can i use read in csh script?
thx (2 Replies)
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)
Hi,
I have a text file with multiple lines, each having data in the below format <DOB>,<ADDRESS>
I have to write a script which reads each line in the text file in loop, assign the values to these variables and do some further processing in it.
Using the following code prints the values... (12 Replies)
Hello,
I am using below code for reading from a file and assigning the values to a variable , but it is loosing the value after the loop , please suggest to retain the value of the variable after the loop ,
while IFS=: read -r line
do
set $dsc=$line
echo 'printing line variable ' $line... (1 Reply)
Discussion started by: ParthThakkar
1 Replies
LEARN ABOUT SUNOS
exec
exec(1) User Commands exec(1)NAME
exec, eval, source - shell built-in functions to execute other commands
SYNOPSIS
sh
exec [argument...]
eval [argument...]
csh
exec command
eval argument...
source [-h] name
ksh
*exec [arg...]
*eval [arg...]
DESCRIPTION
sh
The exec command specified by the arguments is executed in place of this shell without creating a new process. Input/output arguments may
appear and, if no other arguments are given, cause the shell input/output to be modified.
The arguments to the eval built-in are read as input to the shell and the resulting command(s) executed.
csh
exec executes command in place of the current shell, which terminates.
eval reads its arguments as input to the shell and executes the resulting command(s). This is usually used to execute commands generated as
the result of command or variable substitution.
source reads commands from name. source commands may be nested, but if they are nested too deeply the shell may run out of file descrip-
tors. An error in a sourced file at any level terminates all nested source commands.
-h Place commands from the file name on the history list without executing them.
ksh
With the exec built-in, if arg is given, the command specified by the arguments is executed in place of this shell without creating a new
process. Input/output arguments may appear and affect the current process. If no arguments are given the effect of this command is to mod-
ify file descriptors as prescribed by the input/output redirection list. In this case, any file descriptor numbers greater than 2 that are
opened with this mechanism are closed when invoking another program.
The arguments to eval are read as input to the shell and the resulting command(s) executed.
On this man page, ksh(1) commands that are preceded by one or two * (asterisks) are treated specially in the following ways:
1. Variable assignment lists preceding the command remain in effect when the command completes.
2. I/O redirections are processed after variable assignments.
3. Errors cause a script that contains them to abort.
4. Words, following a command preceded by ** that are in the format of a variable assignment, are expanded with the same rules as a vari-
able assignment. This means that tilde substitution is performed after the = sign and word splitting and file name generation are not
performed.
EXIT STATUS
For ksh:
If command is not found, the exit status is 127. If command is found, but is not an executable utility, the exit status is 126. If a redi-
rection error occurs, the shell exits with a value in the range 1-125. Otherwise, exec returns a zero exit status.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWcsu |
+-----------------------------+-----------------------------+
SEE ALSO csh(1), ksh(1), sh(1), attributes(5)SunOS 5.10 17 Jul 2002 exec(1)