Alright, so I'm trying to combine some but not all of my script's parameters into one string. I'm trying to write a script that changes spaces in a file name to underscores, and when the option -r is given, it recursively does it to every file in the folder.
Assuming the file is saved as removespaces.sh, if you run removespaces.sh file with spaces.doc it doesn't really have to care about parameters, I can just use $*
but, when I'm trying to do it for an entire folder I now have -r as $1. So I can't just (be lazy) use $*.. how could I create a string that's equal to $2 to end?
A string of $2 to the end of the parameters:
"${*:2}"
This differs from "${#:2}" in that it concatenates all the arguments, with one space between each. In general, it is possible that neither form is what you want (if, for example, you have files with more than one consecutive space in their name).
Related
I'm writing a script that at one point needs to remove a literal string (no regex matching needed) from a file. Both the string and file path are in script variables.
The problem is that the string is multi-line, and may also contain special characters. Additionally, not all lines in the string are unique in the file (but the string as a whole is), so I cannot go line by line to delete each individual one from the file.
For example, when I echo "$stringToDelete" from my script I get something like:
values(
/the/#quick/[]/"fox",
//jumped/over/the,
//lazy/{},
)
I've tried some approaches using sed and awk but any attempt fails with issues around either the newlines or the special characters. I've seen some answers invoking perl but couldn't get that to work.
Also I can easily read the full file's content into a variable, so the solution doesn't need to edit the file directly - a way to remove the stringToDelete from another string var is fine too.
I am trying write a script to compare one string variable to a list of values, i.e. if the variable matches (exact) to one of the values, then some action needs to be done.
The script is trying to match Unix pathnames, i.e. if the user enters / , /usr, /var etc, then to give an error, so that we do not get accidental corruption using the script. The list of values may change in future due to the application requirements. So I cannot have huge "if" statement to check this.
What I intend to do is that in case if the user enters, any of the forbidden path to give an error but sub-paths which are not forbidden should be allowed, i.e. /var should be rejected but /var/opt/app should be accepted.
I cannot use regex as partial match will not work
I am not sure of using a where loop and an if statement, is there any alternative?
thanks
I like to use associative arrays for this.
declare -A nonoList=(
[/foo/bar]=1
["/some/other/path with spaces"]=1
[/and/so/on]=1
# as many as you need
)
This can be kept in a file and sourced, if you want to separate it out.
Then in your script, just do a lookup.
if [[ -n "${nonoList[$yourString]}" ]] # -n checks for nonzero length
This also prevents you from creating a big file ad grep'ing over it redundantly, though that also works.
As an alternative, if you KNOW there will not be embedded newlines in any of those filenames (it's a valid character, but messy for programming) then you can do this:
$: cat foo
/foo/bar
/some/other/path with spaces
/and/so/on
Just a normal file with one file-path per line. Now,
chkSet=$'\n'"$(<foo)"$'\n' # single var, newlines before & after each
Then in your processing, assuming f=/foo/bar or whatever file you're checking,
if [[ "$chkSet" =~ $'\n'"$f"$'\n' ]] # check for a hit
This won't give you accidental hits on /some/other/path when the actual filename is /some/other/path with spaces because the pattern explicitly checks for a newline character before and after the filename. That's why we explicitly assure they exist at the front and end of the file. We assume they are in between, so make sure your file doesn't have any spaces (or any other characters, like quotes) that aren't part of the filenames.
If you KNOW there will also be no embedded whitespace in your filenames, it's a lot easier.
mapfile -t nopes < foo
if [[ " ${nopes[*]} " =~ " $yourString " ]]; then echo found; else echo no; fi
Note that " ${nopes[*]} " embeds spaces (technically it uses the first character of $IFS, but that's a space by default) into a single flattened string. Again, literal spaces before and behind key and list prevent start/end mismatches.
Paul,
Your alternative work around worked like a charm. I don't have any directories which need embedded space in them. So as long as my script can recognize that there are certain directories to avoid, it does its job.
Thanks
I am copying some specific lines from one file to another.
grep '^stringmatch' /path/sfile-*.cfg >> /path/nfile-*.cfg
Here what's happening: its creating a new file called nfile-*.cfg and copying those lines in that. The file names sfile- * and nfile- * are randomly generated and are generally followed by a number. Both sfile-* and nfile-* are existing files and there is only one such file in the same directory. Only the number that follows is randomly generated. The numbers following in sfile and nfile need not be same. The files are not created simultaneously but are generated when a specific command is given. But some lines from one file to the another file needs to be appended.
I'm guessing you actually want something like
for f in /path/sfile-*.cfg; do
grep '^stringmatch' "$f" >"/path/nfile-${f#/path/sfile-}"
done
This will loop over all sfile matches and create an nfile target file with the same number after the dash as the corresponding source sfile. (The parameter substitution ${variable#prefix} returns the value of variable with any leading match on the pattern prefix removed.)
If there is only one matching file, the loop will only run once. If there are no matches on the wildcard, the loop will still run once unless you enable nullglob, which changes the shell's globbing behavior so that wildcards with no matches expand into nothing, instead of to the wildcard expression itself. If you don't want to enable nullglob, a common workaround is to add this inside the loop, before the grep;
test -e "$f" || break
If you want the loop to only process the first match if there are several, add break on a line by itself before the done.
If I interpret your question correctly, you want to output to an existing nfile, which has a random number in it, but instead the shell is creating a file with an asterisk in it, so literally nfile-*.cfg.
This is happening because the nfile doesn't exist when you first run the command. If the file doesn't exist, bash will fail to expand nfile-*.cfg and will instead use the * as a literal character. This is correct behaviour in bash.
So, it looks like the problem is that the nfile doesn't exist when you start your grep. You'll need to create one.
I'll leave code to others, but I hope the explanation is useful.
I have a folder that was created automatically. The user unintentionally provided smart (curly) quotes as part of the name, and the process that sanitizes the inputs did not catch these. As a result, the folder name contains the smart quotes. For example:
this-is-my-folder’s-name-“Bob”
I'm now trying to rename/remove said folder on the command line, and none of the standard tricks for dealing with files/folders with special characters (enclosing in quotes, escaping the characters, trying to rename it by inode, etc.) are working. All result in:
mv: cannot move this-is-my-folder’s-name-“Bob” to this-is-my-folders-name-BOB: No such file or directory
Can anyone provide some advice as to how I can achieve this?
To get the name in a format you can copy-and-paste into your shell:
printf '%q\n' this*
...will print out the filename in a manner the shell will accept as valid input. This might look something like:
$'this-is-my-folder200\231s-name-200\234Bob200\235'
...which you can then use as an argument to mv:
mv $'this-is-my-folder200\231s-name-200\234Bob200\235' this-is-my-folders-name-BOB
Incidentally, if your operating system works the same way mine does (when running the test above), this would explain why using single-character globs such as ? for those characters didn't work: They're actually more than one byte long each!
You can use shell globbing token ? to match any single character, so matching the smart quotes using ? should do:
mv this-is-my-folder?s-name-?Bob? new_name
Here replacing the smart quotes with ? to match the file name.
There are several possibilities.
If an initial substring of the file name ending before the first quote is unique within the directory, then you can use filename completion to help you type an appropriate command. Type "mv" (without the quotes) and the unique initial substring, then press the TAB key to request filename completion. Bash will complete the filename with the correct characters, correctly escaped.
Use a graphical file browser. Then you can select the file to rename by clicking on it. (Details of how to proceed from there depend on the browser.) If you don't have a graphical terminal and can't get one, then you may be able to do the same with a text-mode browser such as Midnight Commander.
A simple glob built with the ? or * wildcard should be able to match the filename
Use a more complex glob to select the filename, and perhaps others with the same problem. Maybe something like *[^a-zA-Z0-9-]* would do. Use a pattern substitution to assign a new name. Something like this:
for f in *[^a-zA-Z0-9-]*; do
mv "$f" "${f//[^a-zA-Z0-9-]/}"
done
The substitution replaces all appearances of a characters that are not decimal digits, appercase or lowercase Latin letters, or hyphens with nothing (i.e. it strips them). Do take care before you use this, though, to make sure you're not going to make more changes than you intend to do.
I would like to rename many files in this format
abc.123.fits
abcd.1234.fits
efg.12.fits
to this format
abc.fits
abcd.fits
efg.fits
I tried the rename function, but since the part I'm trying to replace is not the same in all files, it did not work. I am using Linux.
for f in *; do mv "$f" "${f%%.*}.${f##*.}"; done`
${f%%.*} removes everything after the first period, including the period. ${f##*.} removes everything before the last period, including the period (i.e. it gets the file extension). Concatenating these two, with a period between them, gives you the desired result.
You can change the * to a more restrictive pattern such as *.fits if you don't want to rename all files in the current directory. The quotes around the parameters to mv are necessary if any filenames contain whitespace.
Many other variable substitution expressions are available in bash; see a reference such as TLDP's Bash Parameter Substitution for more information.