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Full Discussion: Need bash script to use a sed command as a variable
Top Forums Shell Programming and Scripting Need bash script to use a sed command as a variable Post 303038031 by Scrutinizer on Thursday 22nd of August 2019 01:53:54 AM
Old 08-22-2019
Note that with standard sed (non-GNU) there needs to be a ; before the trailing }:
Code:
ip=$(sed -n '/inet */{s///p;q;}' config.boot)

or we can avoid the braces by using negation style:
Code:
ip=$(sed '/inet */!d; s///; q' config.boot)

--
Alternatively we can avoid the sub shell / external command altogether with just standard shell:
Code:
until [ "$inet" = inet ]; do
  read inet ip
done < config.boot

--
Note also that these are all naive approaches without knowing what the format of config.boot looks like. Also, if the are more inet configs in the same file, these will only pick the first one indiscriminately.
Last edited by Scrutinizer; 08-22-2019 at 03:16 AM..
 

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LEARN ABOUT DEBIAN

rbash

RBASH(1)						      General Commands Manual							  RBASH(1)

NAME

       rbash - restricted bash, see bash(1)

RESTRICTED SHELL

       If  bash  is  started with the name rbash, or the -r option is supplied at invocation, the shell becomes restricted.  A restricted shell is
       used to set up an environment more controlled than the standard shell.  It behaves identically to bash with the exception that the  follow-
       ing are disallowed or not performed:

       o      changing directories with cd

       o      setting or unsetting the values of SHELL, PATH, ENV, or BASH_ENV

       o      specifying command names containing /

       o      specifying a file name containing a / as an argument to the .  builtin command

       o      specifying a filename containing a slash as an argument to the -p option to the hash builtin command

       o      importing function definitions from the shell environment at startup

       o      parsing the value of SHELLOPTS from the shell environment at startup

       o      redirecting output using the >, >|, <>, >&, &>, and >> redirection operators

       o      using the exec builtin command to replace the shell with another command

       o      adding or deleting builtin commands with the -f and -d options to the enable builtin command

       o      using the enable builtin command to enable disabled shell builtins

       o      specifying the -p option to the command builtin command

       o      turning off restricted mode with set +r or set +o restricted.

       These restrictions are enforced after any startup files are read.

       When a command that is found to be a shell script is executed, rbash turns off any restrictions in the shell spawned to execute the script.

SEE ALSO

       bash(1)

GNU Bash-4.0							    2004 Apr 20 							  RBASH(1)
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