Use of exec 2>/dev/null

Shell Programming and Scripting
1

I have a script for which I am getting useless error messages. It is composed mostly of case statements. I placed exec 2>/dev/null at the top of the script and it works totally but the problem is that it also redirects the read command input to the /dev/null. So if a user responds to "type your name," this gets redirected to /dev/null. Is there a way to make the read command still show the input when a user types and the /dev/null to still work for all error messages? I've tried different ways but I have had no luck. The user needs to be able to see what they are typing.

2

I haven't known read to behave like that. Which OS and shell are you using? Can you post the read statement?

$ read A
blah
$ echo $A
blah
$ exec 2> /dev/null
read B
blahblah
echo $B
blahblah
exec 2>&1
$

I can imagine the behaviour you describe using stty, but not using exec.

Anyhow, if read is the problem, perhaps redirecting output to standard output (with -u1), if that's allowed, is an option.

Although read doesn't read from standard output!

3

This is what part of the script looks like. When folks are typing, now they can't see the date or the directory name

while [ $y=1 ]; do
exec 2>/dev/null
    case ${answer} in
    "[Xx][Aa][Nn][Gg][Qq]"|1)
              mode="entry"
        echo -e "Specify an Option\n1. name\t2. directory\t3. sum"
        read option
        case ${option} in
            "[Aa][Dd][Dd]"|1)
                echo "enter directory name in lowercase"
                read -e directory
                echo "type the start date"                r\
                read -e startdate

---------- Post updated at 11:55 AM ---------- Previous update was at 10:48 AM ----------

Not sure how to use u1 switch to redirect? Can you please demonstrate with a command?

---------- Post updated at 12:00 PM ---------- Previous update was at 11:55 AM ----------

I tried

read $directory print -u1 "fd1"

but this did not do anything. Probably I don't know how to use this command switch -u1

4

So it seems you're using Bash.

You could remove the -e option, or use exec before and after the read (or case statement) to temporarily stop redirection.

(that -u1 thing doesn't work)

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