Using read to prompt for editable user input in Bash 3

[woodson2]

Below is a simple script to prompt for user input while suggesting an editable default value at the prompt:



shortname=user1
read -e -i $shortname -p "Please enter the username you would like to add: " input

USERNAME="${input:-shortname}"
Output:

Please enter the username you would like to add: user1

The above is the expected and working output in BASH 4

If I try this same code in BASH 3 it doesn't work because this version does not support the "-i" switch.

I need some help getting the same result in BASH 3.
Thanks

[Habitual]

While both the bash [34] versions I checked with "man bash", both read
"-i If the -i option is present, the shell is interactive."

but it barked on 4 when I tried your code.

I tried this (alternate?) method and it worked in both bash[34]:

echo -n "user...? " && read USER && echo $USERWhat that does to this snippet, I have no idea, sorry.

USERNAME="${input:-shortname}"Smarter people than I are likely to answer soon enough.

Have a Great Day!

Edit: I saw this... (http://www.linuxquestions.org/questions/programming-9/using-read-to-prompt-for-editable-user-input-in-bash-3-a-4175438942/) earlier today.

[woodson2]

Thanks for replying however I think you misunderstand.

The "i" switch is a option passed to the "read" command which is a bash built-in.

The switch wasn't introduced until BASH ver 4.

This following code sets the $USERNAME variable to the default if enter is pressed at the prompt. If the user doesn't want the default suggestion and enters text it accounts for that as well.


USERNAME="${input:-shortname}

[Habitual]

..The switch wasn't introduced until BASH ver 4.


CentOS release 5.8
GNU bash, version 3.2.25(1)-release (i686-redhat-linux-gnu)
"man bash" definitely has an entry that reads
"-i If the -i option is present, the shell is interactive."
under Options:

Again, smarter people than I are just around the corner. :)

[Vaphell]

it's about read. OP says that read -i doesn't work in older bash versions.

I don't know if that's possible to achieve in trivial way
i'd suggest lame fallback eg

read -p "enter name (dafault $shortname)" input
username=${input:-shortname}

also i'd avoid common word variables in all-caps. Overriding env variables is not cool and USERNAME is awfully close to USER

[woodson2]

it's about read. OP says that read -i doesn't work in older bash versions.

I don't know if that's possible to achieve in trivial way
i'd suggest lame fallback eg

read -p "enter name (dafault $shortname)" input
username=${input:-shortname}also i'd avoid common word variables in all-caps. Overriding env variables is not cool and USERNAME is awfully close to USER


Yea , it looks like there no other way to skin this cat.

Thanks.