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Top Forums Shell Programming and Scripting Problem with while loop reading every line of a text file Post 302949222 by neutronscott on Wednesday 8th of July 2015 09:12:43 AM
Old 07-08-2015
both of these read operations work on the same stdin. you need to assign to a different fd and use that for one of them. the easiest way to do this is to ditch the useless use of cat (uuoc award).

Code:
while read line <&9; do
  echo "$line"
  echo "press enter key"
  read
done 9<passwd_sample

Now we redirect passwd_sample into fd 9 for the entire while block, yet only the first read operation operates on fd 9. in this way, we'll keep our position in the file with each iteration and read line-by-line but not interfere with the read that wants input from the terminal.

if you're using bash, you can use read -s -N 1 for grabbing a single key. otherwise you'll need to press enter rather than "any" key.
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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 filename 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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