macOS need help with script

[twoodcc]

ok, so what i want to do is make some sort of script, either applescript or shell script, that will do the following:

take out from a command in the terminal
put that output into a text file already on my computer.

the only thing is that i need to put the output in the file kinda weird: i need to take it and put each character of output on a new line, but not create new lines

example:

take output of command 'uptime' (up 32 days, 23:09)
place in file 'myFile'

output:
...
key u
key p
key space
key 3
key 2
key space
key d
...

anyone have any idea on how to do this?

thanks in advance

 

[SC68Cal]

This sounds like a homework assignment. Whatever.

import sys
from subprocess import *
def spaceify(str):
	output = ""
	i = 0
	while i < len(str):
		if str[i] != "\n":
			output += str[i] + "\n"
		else:
			output += str[i] 
		i+=1
	return output

pipe = Popen(sys.argv[1], shell=True, stdout=PIPE).stdout
outfile = open(sys.argv[2],"a")
ln = pipe.readline()
while ln != "":
	outfile.write(spaceify(ln))
	ln = pipe.readline()
outfile.close()

Save that code into a new file with a .py extension

Invoke it in the shell as:

python <name saved file>.py <command to invoke> <name of file to save in>

If the command you're invoking has extra flags, enclose it in quotations.

Now give me $20.

 

[twoodcc]

thank you for the reply!

i ran this script, and it did write to the file, but not quite was i was looking for. it put the output of the command at the bottom of the file, one character on each line.

what i need is to add "key " to each line of output from the command, and place that output in the file starting at "key n" where n = some number 0-9.

so basically, the what the script that i ran did was this:

u

p

t

i

m

e

but what i wanted was this:

key u
key p
key t
key i
key m
key e

and play that when you get to "key 0" or key "1" or "key 2" etc

 

[SC68Cal]

What is this script for? This really has no real-world value so it must be some sort of homework assignment. Is this supposed to be a histogram of letters used?

 

[twoodcc]

What is this script for? This really has no real-world value so it must be some sort of homework assignment. Is this supposed to be a histogram of letters used?

it is not a homework assignment. it's something that i'm trying to experiment with. i also am trying to use the terminal more, and would like to learn shell scripting

 

[twoodcc]

here is what someone else made, and i altered a little bit:

#!/bin/bash

output=$(uptime)
length=${#output}

for ((i=1; i<=length; i++))
do
character=$(echo $output | cut -c$i)
case "$character" in
[[:space:]]) echo "key <space>";;
*) echo "key $character";;
esac
done

now this does exactly what i want, except it just prints to the screen. so how can i make this write to a file?

 

[twoodcc]

would i just put " >> filename" after the statements to write to the file? i did this, and it worked, but it writes to the bottom of the file.

so how would i write to a certain part in the file?

i've been trying to figure out if statements for unix scripts, but am having a little trouble

 

[twoodcc]

well i have been messing around, and here is what i have so far:

#!/bin/bash

output=$(uptime)
length=${#output}

cat tim | while read LINE
do
if [LINE == "key 0"]; then
for ((i=1; i<=length; i++))
do
character=$(echo $output | cut -c$i)
case "$character" in
[[:space:]]) echo "key <space>" >> tim;;
*) echo "key $character" >> tim;;
esac
done

fi
done

the file name is 'tim'. but i get an error on line 8 with the if statement. what am i doing wrong?

 

[twoodcc]

okay, i am getting somewhere. this is the code that i have now:

#!/bin/bash

output=$(uptime)
length=${#output}

cat tim | while read LINE
do
if [ "${LINE}" == "key 0" ]; then
for ((i=1; i<=length; i++))
do
character=$(echo $output | cut -c$i)
case "$character" in
[[:space:]]) echo "key <space>" >> tim;;
*) echo "key $character" >> tim;;
esac
done

fi
done

now, this finds every line in the file that is "key 0", but then writes the output at the bottom of the file. it does this for every "key 0". my logic here is wrong.

what i want: i have a block of text that i want to replace with this output. starting with the first line that is "key 0", and write the block of code once, and stop

 

[AUFan]

would i just put " >> filename" after the statements to write to the file? i did this, and it worked, but it writes to the bottom of the file.

so how would i write to a certain part in the file?

i've been trying to figure out if statements for unix scripts, but am having a little trouble

If you want to write to a new file or overwrite a new file (via terminal) you would do

[terminal commands] > filename

ls -l -a > fileslist

That takes the long listing of every single file or subdirectory in whatever directory you are located in and instead of displaying the output in the terminal dumps it into a new file called fileslist that you could then open with something like TextEdit. (It will also overwrite existing files if you happen to use the same filename as some other file in the same directory)

ls -l -a >> fileslist

This does the same thing as the prior section but instead of overwriting an existing file it appends it (the content is added to the end of the existing file).

 

[twoodcc]

If you want to write to a new file or overwrite a new file (via terminal) you would do

[terminal commands] > filename

ls -l -a > fileslist

That takes the long listing of every single file or subdirectory in whatever directory you are located in and instead of displaying the output in the terminal dumps it into a new file called fileslist that you could then open with something like TextEdit. (It will also overwrite existing files if you happen to use the same filename as some other file in the same directory)

ls -l -a >> fileslist

This does the same thing as the prior section but instead of overwriting an existing file it appends it (the content is added to the end of the existing file).

thanks for the reply. i know this command, but this doesn't allow me to overwrite lines in the middle of the file.