All,
I am running BASH in Solaris 10
I have the following shell script that loops in a directory depending on the presence of CSV files.
The problem is with this piece of code is that it still does one loop even if there is no CSV files in that directory and then calls SQL loader.
SQLLoader then produces a log file because there is no file to process and this is beginning to mess up my directory filling it with log files.
for file in *.csv ;
do
echo "SQLLoader is reading : " $file
sqlldr <User>/<Password>#<DBURL>:<PORT>/<SID> control=sqlloader.ctl log=$inbox/$file.log data=$inbox/$file
done
How do I stop it going into a loop if there is no CSV files in that directory of $inbox
Say:
shopt -s nullglob
before your for loop.
This is not the default, and saying for file in *.csv when you don't have any matching files expands it to *.csv.
Quoting from the documentation:
nullglob
If set, Bash allows filename patterns which match no files to expand to a null
string, rather than themselves.
Use find to search files
for file in `find -name "*.csv"` ;
First off, using nullglob is the correct answer if it is available. However, a POSIX-compliant option is available.
The pattern will be treated as literal text if there are no matches. You can catch this with a small hack:
for file in *.csv; do
[ -f "$file" ] || break
...
done
When there are no matches, file will be set to the literal string *.csv, which is not the name of a file, so -f "$file" will fail. Otherwise, file will be set in turn to the name of each file matching the pattern, and -f "$file" will succeed every time. Note this will work even if there is an file named *.csv. The drawback is that you have to make a redundant test for each existing file.
Related
I've got some files in a directory with a standard format, I'm looking to use a txt file with part of the filenames to extend them through * then finally add on a .gz tag as an output
For example, a file called 1.SNV.111-T.vcf in my directory, I have 111-T in my txt file.
#!/bin/bash
while getopts f: flag
do
case "${flag}" in
f) file=${OPTARG};;
esac
done
while IFS="" read -r p || [ -n "$p" ]
do
vcf="*${p}.vcf"
bgzip -c ${vcf} > ${vcf}.gz
done < $file
This will successfully run bgzip but actually save the output to be:
'*111-T.vcf.gz'
So adding .gz at the end has "deactivated" the * character, as pointed out by Barmar this is because there isn't a file in my directory called 1.SNV.111-T.vcf.gz so the wildcard is inactivated, please can anyone help?
I'm new to bash scripting but I assume there must be some way to save the "absolute" value of my vcf variable so that once it has found a match the first time, it's now a string that can be used downstream? I really cant find anything online.
The problem is that wildcards are only expanded when they match an existing file. You can't use a wildcard in the filename you're trying to create.
You need to get the expanded filename into the vcf variable. You can do it this way:
vcf=$(echo *"$p.vcf")
bgzip -c "$vcf" > "$vcf.gz"
I'm writing a small piece of code that checks for .mov files in a specific folder over 4gb and writes it to a log.txt file by name (without an extension). I'm then reading the names into a while loop line by line which signals some archiving and copying commands.
Consider a file named abcdefg.mov (new) and a corresponding folder somewhere else named abcdefg_20180525 (<-*underscore timestamp) that also contains a file named abcedfg.mov (old).
When reading in the filename from the log.txt, I strip the extension to store the variable "abcdefg" ($in1) and i'm using that variable to locate a folder elsewhere that contains that matching string at the beginning.
My problem is with how the mv command seems to support a wild card in the "source" string, but not in the "destination" string.
For example i can write;
mv -f /Volumes/Myshare/SourceVideo/$in1*/$in1.mov /Volumes/Myshare/Archive
However a wildcard on the destination doesn't work in the same way. For example;
mv -f /Volumes/Myshare/Processed/$in1.mov Volumes/Myshare/SourceVideo/$in1*/$in1.mov
Is there an easy fix here that doesn't involve using another method?
Cheers for any help.
mv accepts a single destination path. Suppose that $in1 is abcdfg, and that $in1* expands to abcdefg_20180525 and abcdefg_20180526. Then the command
mv -f /dir1/$in1 /dir2/$in1*/$in1.mov
will be equivalent to:
mv -f /dir1/abcdefg.mov /dir2/abcdefg_20180526/abcdefg.mov
mv -f /dir1/abcdefg.mov /dir2/abcdefg_20180526/abcdefg.mov
mv -f /dir2/abcdefg_20180525/abcdefg.mov /dir2/abcdefg_20180526/abcdefg.mov
Moreover, because the destination file is the same in all three cases, the first two files will be overwritten by the third.
You should create a precise list and do a precise copy instead of using wild cards.
This is what I would probably do, generate a list of results in a file with FULL path information, then read those results in another function. I could have used arrays but I wanted to keep it simple. At the bottom of this script is a function call to scan for files of EXT mp4 (case insensitive) then writes the results to a file in tmp. then the script reads the results from that file in another function and performs some operation (mv etc.). Note, if functions are confusing , you can just remove the function name { } and name calls and it becomes a normal script again. functions are really handy, learn to love them!
#!/usr/bin/env bash
readonly SIZE_CHECK_LIMIT_MB="10M"
readonly FOLDER="/tmp"
readonly DESTINATION_FOLDER="/tmp/archive"
readonly SAVE_LIST_FILE="/tmp/$(basename $0)-save-list.txt"
readonly EXT="mp4"
readonly CASE="-iname" #change to -name for exact ext type upper/lower
function find_files_too_large() {
> ${SAVE_LIST_FILE}
find "${FOLDER}" -maxdepth 1 -type f "${CASE}" "*.${EXT}" -size +${SIZE_CHECK_LIMIT_MB} -print0 | while IFS= read -r -d $'\0' line ; do
echo "FOUND => $line"
echo "$line" >> ${SAVE_LIST_FILE}
done
}
function archive_large_files() {
local read_file="${SAVE_LIST_FILE}"
local write_folder="$DESTINATION_FOLDER"
if [ ! -s "${read_file}" ] || [ ! -f "${read_file}" ] ;then
echo "No work to be done ... "
return
fi
while IFS= read -r line ;do
echo "mv $line $write_folder" ;sleep 1
done < "${read_file}"
}
# MAIN (this is where the script starts) We just call two functions.
find_files_too_large
archive_large_files
it might be easier, i think, to change the filenames to the folder name initially. So abcdefg.mov would be abcdefg_timestamp.mov. I can always strip the timestamp from the filename easy enough after its copied to the right location. I was hoping i had a small syntax issue but i think there is no easy way of doing what i thought i could...
I think you have a basic misunderstanding of how wildcards work here. The mv command doesn't support wildcards at all; the shell expands all wildcards into lists of matching files before they get passed to the mv command as wildcards. Furthermore, the mv command doesn't know if the list of arguments it got came from wildcards or not, and the shell doesn't know anything about what the command is going to do with them. For instance, if you run the command grep *, the grep command just gets a list of names of files in the current directory as arguments, and will treat the first of them as a regex pattern ('cause that's what the first argument to grep is) to search the rest of the files for. If you ran mv * (note: don't do this!), it will interpret all but the last filename as sources, and the last one as a destination.
I think there's another source of confusion as well: when the shell expands a string containing a wildcard, it tries to match the entire thing to existing files and/or directories. So when you use Volumes/Myshare/SourceVideo/$in1*/$in1.mov, it looks for an already-existing file in a matching directory; AIUI the file isn't there yet, there's no match. What it does in that case is pass the raw (unexpanded) wildcard-containing string to mv as an argument, which looks for that exact name, doesn't find it, and gives you an error.
(BTW, should there be a "/" at the front of that pattern? I assume so below.)
If I understand the situation correctly, you might be able to use this:
mv -f /Volumes/Myshare/Processed/$in1.mov /Volumes/Myshare/SourceVideo/$in1*/
Since the filename isn't supplied in the second string, it doesn't look for existing files by that name, just directories with the right prefix; mv will automatically retain the filename from the source.
However, I'll echo #Sergio's warning about chaos from multiple matches. In this case, it won't overwrite files (well, it might, but for other reasons), but if it gets multiple matching target directories it'll move all but the last one into the last one (along with the file you meant to move). You say you're 100% certain this won't be a problem, but in my experience that means that there's at least a 50% chance that something you'd never have thought of will go ahead and make it happen anyway. For instance, is it possible that $in1 could wind up empty, or contain a space, or...?
Speaking of spaces, I'd also recommend double-quoting all variable references. You want the variables inside double-quotes, but the wildcards outside them (or they won't be expanded), like this:
mv -f "/Volumes/Myshare/Processed/$in1.mov" "/Volumes/Myshare/SourceVideo/$in1"*/
Hi I have a file that sorts some code and reformats it. I have over 200 files to apply this to with incremental names run001, run002 etc. Is there a quick way to write a shell script to execute this file over all the files? The executable creates a new file called run001an etc so just running over all files containing run doesnt work, how do i increment the file number?
Cheers
how about:
for i in ./run*; do
process_the_file $i
done
which is valid Bash/Ksh
To be more specific with run### files you can have
for file in dir/run[0-9][0-9][0-9]; do
do_something "$file"
done
dir could simply be just . or other directories. If they have spaces, quote them around "" but only the directory parts.
In bash, you can make use of extended patterns to generate all number matches not just 3 digits:
shopt -s extglob
for file in dir/run+([0-9]); do
do_something "$file"
done
I am very new with linux usage maybe this is my first time so i hope some detailed help please.
I have more than 500 files in multiple directories on my server (Linux) I want to change their extensions to .xml using bash script
I used a lot of codes but none of them work some codes i used :
for file in *.txt
do
mv ${file} ${file/.txt}/.xml
done
or
for file in *.*
do
mv ${file} ${file/.*}/.xml
done
i do not know even if the second one is valid code or not i tried to change the txt extension beacuse the prompt said no such file '.txt'
I hope some good help for that thank you
Explanation
For recursivity you need Bash >=4 and to enable ** (i.e. globstar) ;
First, I use parameter expansion to remove the string .txt, which must be anchored at the end of the filename (%) :
the # anchors the pattern (plain word or glob) to the beginning,
and the % anchors it to the end.
Then I append the new extension .xml
Be extra cautious with filename, you should always quote parameters expansion.
Code
This should do it in Bash (note that I only echothe old/new filename, to actually rename the files, use mv instead of echo) :
shopt -s globstar # enable ** globstar/recursivity
for i in **/*.txt; do
[[ -d "$i" ]] && continue; # skip directories
echo "$i" "${i/%.txt}.xml";
done
If its a matter of a one or two sub-directories, you can use the rename command:
rename .txt .xml *.txt
This will rename all the .txt to .xml files in the directory from which the command is executed.
If all the files are in same directory, it can be done using a single command. For example you want to convert all jpg files to png, go to the related directory location and then use command
rename .jpg .png *
I wanted to rename "file.txt" to "file.jpg.txt", used rename easy peezy:
rename 's/.txt$/.jpg.txt/' *.txt
man rename will tell you everything you need to know.
Got to love Linux, there's a tool for everything :-)
passing command line argument for dir path
#!/bin/sh
cd $1
names_1=`ls`
for file in ${names_1}
do
mv ${file} ${file}.jpg
done
I have written a shell script which picks all the files recursively inside all the directories and prepared a report with the file last modified, size.
The problem that I am facing, there are few files with name as "User Interface"(space in between). How to use there files in the for loop of the shell script and fetch the files and directories inside this.
Thanks in advance
Just put the file name variable between double quotes "$FILENAME"
You're probably trying to use something like for file in $(command). Instead, use a while read loop or a for loop with globbing. Make sure you quote variables that contain filenamess.
#!/bin/sh
command | while read -r file
do
something_with "$file"
done
or, in shells that support process substitution:
#!/bin/bash
while read -r file
do
something_with "$file"
done < <(command)
If you're simply iterating over a list of files:
for file in "$dir"/*
do
something_with "$file"
done
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