My bash script asks user for their first name, last name, address and phone number and writes this information that is input by the user to a file of the format "firstname.lastname"; however I want to repeat this a number of times (I actually wanted to do something like a do..while loop where it runs atleast one time and asks user if they want to continue creating accounts or not but I see there is no do...while for bash it seems). So when I execute this bash script in the terminal it will ask for how many accounts to be made and I provide all the input but the it only runs one time. What am I doing wrong? Here is my script.
#!bin/bash
echo "How many accounts are you creating?"
read num
echo "Enter first name"
read fName
echo "Enter last name"
read lName
echo "Enter address"
read add
echo "Enter phone number"
read phn
echo "Enter gender m for male and f for female"
read gender
if [ "$gender" == "m" ]
then
sex="male"
elif [ "$gender" == "f" ]
then
sex="female"
else
echo"Invalid gender. Restart the script and enter a valid gender"
exit 0
fi
for (( i = 0; i<=num; i++))
do
cat > $fName.$lName <<-EOF
Full Name: $fName $lName
Address: $add
Phone number: $phn
Gender: $gender
EOF
done
zerobandwidth's answer is correct, but as an alternative answer, it is in fact quite easy to do what you initially wanted to do:
while true; do
# Your account creation code goes here
echo "Create another account (y/n)?"
read another
if [ "$another" != y ]; then
break
fi
done
Put your input code inside the loop, or wrap that code in a function and call the function inside the loop.
Related
I'm trying to combine two lists containing names (if available) and emails with a standard email text in bash (shell)
(I had to delete the irrelevant code as it contains some private info, so some of the code might look unusal.)
The first half of the code checks if there is a name list along with the email list.
The second half combines only the email address and text if no name is available, if the name list is available it also 'tries' to combine the name, email and text.
f1 = email list and f2 = name list.
As you can see in the first half of the code below, $f2 should show the names if the list is available but it does not show anything in the log file.
I been trying to sort this problem out for two days but nothing has worked. When names are available it always outputs as "Hello ..." when it should be "Hello John D..."
#FIRST HALF
if [ "$names" = "no" ]
then
text="Hello..."
elif [ "$names" = "yes" ]
then
text="Hello $f2..."
fi
#SECOND HALF
if [ "$names" = "no" ]
then
for i in $(cat $emaillist); do
echo "$text" >> /root/log
echo "$i" >> /root/log
done
elif [ "$names" = "yes" ]
then
paste $emaillist $namelist | while IFS="$(printf '\t')" read -r f1 f2
do
echo "$text" >> /root/log
echo "$f1" >> /root/log
done
fi
When you run text="Hello $f2", $f2 is looked up at the time of the assignment; an exact string is assigned to text, and only that exact string is used later, on echo "$text".
This is very desirable behavior: If shell variables' values could run arbitrary code, it would be impossible to write shell scripts that handled untrusted data safely... but it does mean that implementing your program requires some changes.
If you want to defer evaluation (looking up the value of $f2 at expansion time rather than assignment), don't use a shell variable at all: Use a function instead.
case $names in
yes) write_greeting() { echo "Hello $name..."; };;
*) write_greeting() { echo "Hello..."; };;
esac
while read -r name <&3 && read -r email <&4; do
write_greeting
echo "$email"
done 3<"$namelist" 4<"$emaillist" >>/root/log
Some enhancements in the code above:
You don't need paste to read from two streams in lockstep; you can simply open them on different file descriptors (above, FDs 3 and 4 are chosen; only 0, 1 and 2 are reserved, so larger numbers could have been selected as well) with a separate read command for each.
Opening your output sink only once for the entire loop (by putting the redirection after the done) is far more efficient than re-opening it every time you want to write a single line.
Expansions, such as "$namelist" and "$emaillist", are always quoted; this makes code more reliable if dealing with filenames with unusual characters (including spaces and glob expressions), or if IFS is at a non-default value.
Am writing a script.Eg:
echo "my name is 'read' and am from 'read' city" > outfile.txt
When it runs it's not printing the sentence first, i.e my name is. Rather it's asking first to enter 2 inputs for 2 read commands used, then its forming the complete sentence like "my name is sudhir and am from vizag city"
I want script to execute 1st "my name is read(ask for input) and am from read(ask for another input) city" and after giving inputs it should redirect to outfile.txt in one shot.
How to handle this? Is it feasible to achieve in single sentence?
Because I want to use same logic for 480 questions all in one file and persons how don't have any scripting knowledge should able to add more questions taking reference of previous questions present in same file.
There isn't a pretty way to do this, since read writes the newline character from the input to the terminal, but we can do this in two passes.
Get the input from the user
Write the results to the file
You could put the following in a script
#!/bin/bash
echo -n 'my name is '; read -r name
echo -n ' and I am from '; read -r city
echo ' city'
printf "my name is %s and I am from %s city\n" \
"$name" "$city" > output.txt
And to the user it would look like this
my name is sudhir
and I am from vizag
city
But it would be like this in the file
my name is sudhir and I am from vizag city
You can write a function that takes a string with placeholders and asks the user to input for each of them:
#!/bin/bash
fill() {
arg="$*"
result=""
while [[ "$arg" =~ ([^_]*)(_+)(.*) ]]
do
read -rp "${BASH_REMATCH[1]# }${BASH_REMATCH[2]}: " input
result+="${BASH_REMATCH[1]}${input}"
arg="${BASH_REMATCH[3]}"
done
result+="$arg"
printf '%s\n' "$result"
}
exec > outputfile
fill "My name is ____ and I am from ___."
fill "My new years resolution is ____."
Example:
$ ./myscript
My name is ____: Sudhir
and I am from ___: Vizag
My new years resolution is ____: learning Bash instead of asking SO to write my scripts
$ cat outputfile
My name is Sudhir and I am from Vizag.
My new years resolution is learning Bash instead of asking SO to write my scripts.
Welcome all,
I am required to prompt the user to enter "all, long, human or alh". I have developed some code however there is an error. I have used shellcheck.net to check whether the syntax of my code is appropriate.
the program itself should give a file and directory listing (based on the command line parameter received) and also show an error message if one of the options above is not selected.
”all” - do not hide entries starting with .
“long” - use a long listing format
“human” - use a long listing format and print sizes in human readable
format
“alh” – do all of the above
This is my code:
read -p "Please enter all, long, human or alh: " userInput
if [ -z "$userInput" ];
then
print f '%s/n' "Input is not all, long human or alh"
exit 1
else
printf "You have entered %s " "$UserInput"
fi
the code itself works, however it does not show any directory listings based on the chosen parameter.
Output:
Please enter all, long, human or alh: all
You have entered all
I'd use the case command
#!/bin/bash
read -p "Please enter all, long, human or alh: " userInput
case "$userInput" in
(all) flags=a;;
(long) flags=l;;
(human) flags=lh;;
(alh) flags=alh;;
(*) printf '%s\n' "Input is not all, long human or alh"
exit 1;;
esac
ls -$flags
Or, you can store the flags in an associative array:
#!/bin/bash
read -p "Please enter all, long, human or alh: " userInput
declare -A flags
flags=([all]=a
[long]=l
[human]=lh
[alh]=alh
)
flag=${flags[$userInput]}
if [[ -z $flag ]] ; then
printf '%s\n' "Input is not all, long human or alh"
exit 1
fi
ls -$flag
As the title says, I'm trying to make a program that has a user input a number 1-7, then displays the appropriate command for each number.
The problem I'm having is finding a good way to set each number to a command.
At first, I thought about doing something like this.
OSI=$(uname -a)
echo $OSI
But the problem with that is actually implementing it into a loop. Let's say the user is prompted like so:
"Enter a number:"
The user enters the number 1, and number 1 is the OSI. Well if a user picks the number 2, it needs to display a different command and so forth.
This is a little bit too complicated for a beginner like myself. I've read through forums and different posts, but I cannot figure out the right commands to make this happen.
I tried doing something like this and it failed miserably:
#!/bin/bash
read -p "Enter a number:" n1 n2 n3 n4 n5 n6 n7
if n1=1; then
uname - a
else n2=2; "different command"
fi
I realize I'm completely garbage at bash. I'm not asking for anyone to solve this, just give me some pointers in a way that makes sense to me.
Thanks.
Give this tested version a try:
#!/bin/bash --
printf "menu items:\n 1) uname -a\n 2) date\n q) exit\n"
read -p "Enter your choice: " response
if [ -z "$response" ] ; then
printf "Choice invalid\n"
exit 1
fi
if [ "$response" = q ] ; then
exit 0
fi
if [ "$response" = 1 ] ; then
uname -a
elif [ "$response" = 2 ] ; then
date
else
printf "Choice invalid\n"
fi
As written by #EdMorton case is a better option.
I'm currently learning Linux and as an homework, we have to create a few basic shell scripts. Nothing especially complicated but this one is giving me headaches. Here's my code :
until [ "$toPrint" == 'fin' ]
do
echo "Enter file name to print out :" ; read toPrint
sh ./afficher.sh "$toPrint"
done
Basically, I have another script called afficher.sh (I'm french so don't mind the french language used) and it reads whatever file name it gets as a parameter. However, the moment I type "fin", everything is supposed to stop except it still tries to print the file called "fin". I read a bit about the until loop on Internet and once it becomes True, it should stop, which is not my case...
Personally, I'd implement this like so -- with a while loop, not an until loop, and checking for the exit condition separately and explicitly:
while true; do
echo "Enter file name to print out :" ; read toPrint
[ "$toPrint" = fin ] && break
sh ./afficher.sh "$toPrint"
done
If you really want to use the loop's condition, you can do that:
while echo "Enter file name to print out :";
read toPrint &&
[ "$toPrint" != fin ]; do
sh ./afficher.sh "$toPrint"
done
...but personally, I'm less fond of this on aesthetic grounds.
You check the condition at the top of the loop, but you enter the value in the middle of the loop. The next thing you do after reading the value is always pass it to afficher.sh and then once that is done you check its value to see if you should stop. If you don't want to run afficher.sh on the fin value, you'll need to make sure your control flow allows you to do the comparison before you invoke afficher.sh.