ls -lAtr /data/log.* | tail -1 | awk '{ printf $9 }' > $logfile
echo $logfile
cat $logfile # I want to cat the content of this log file, but this wouldn't work
logfile2=/usr/some/path/text.log
echo $logfile2
cat $logfile2 # This work
I am new to shell programming, I wondering how do I convert the logfile into something like logfile2(Did I ask the right question?), so that I can treat it like a file and read from it.
Think you're looking for (works in bash as well)
logfile2="$(</usr/some/path/text.log)"
From ksh man page
$(cat file) can be replaced by the equivalent but faster $(<file).
e.g.
> cat text.log
line 1
line 2
> ksh
> logfile2="$(<text.log)"
> echo "$logfile2"
line 1
line 2
Are you trying to store the result of ls|tail|awk in $logFile? If so:
logFile=$(ls -lAtr /data/log.* | tail -1 | awk '{ printf $9 }')
However, you shouldn't parse the output of ls.
Related
Would it be possible to print the filename used to redirect STDERR, given the sample command below:
command.sh 2>file.err
Code in command.sh:
#!/bin/sh
ls -l non_existing_file.txt
echo "STDERR file is: $stderrFilename" # variable should print file.err
It's a little risky, but you could try parsing AIX's procfiles output. It involves capturing the major and minor numbers of the stderr device, along with the inode number, then looking for the corresponding device, its mountpoint, and then using find to look for the file with the given inode number:
#!/bin/sh
dev=$(procfiles $$ | awk '$1 == "2:" { print substr($4, 5) }')
inode=$(procfiles $$ | awk '$1 == "2:" { print substr($5, 5) }')
major=${dev%%,*}
minor=${dev##*,}
if [ "$major}" -eq 0 ]
then
echo I give up, the major number is zero
exit 1
fi
for file in /dev/*
do
[ -b "$file" ] || continue
if istat "$file" | grep -q "^Major Device ${major}.*Minor Device ${minor}$"
then
break
fi
done
fs=$(mount | awk '$1 == "'"${file}"'" { print $2 }')
stderrFilename=$(find "$fs" -inum "$inode")
I made a solution using history. Not sure if there is an easier way to do this ( or a proper one).
#!/bin/sh
stderrfname=`history | tail -1 | awk '{ print $3 }' | sed "s/.*>//"`
echo "STDERR file is: $stderrfname"
I was basically trying to compare two files and as part of that I assigned the cksum of the file to a variable . But when I try to compare it, it did not work. I realized that when I tried to read the variable nothing gets printed out
The below commands worked just fine
s.joseph#VA-S-JOSEPH-900 /cygdrive/c/users/Anuprita
$ test=`cksum interface2 | awk -F" " '{ print $1 }'`
s.joseph#VA-S-JOSEPH-900 /cygdrive/c/users/Anuprita
$ echo "$test"
3021988741
But when these are part of a script and I try to echo $var, nothing gets printed
$ for i in `ls interface*`;
do chksum1=`cksum $i | awk -F" " '{ print "'$1'" }'`;
echo "$chksum1";
done
s.joseph#VA-S-JOSEPH-900 /cygdrive/c/users/Anuprita
$
I am using bash shell
Without assigning it to any variable, the output is as shown below
for i in interface*; do echo "interface=\"$i\""; cksum "$i"; done
interface="interface11"
4113442291 111 interface11
interface="interface17"
1275738681 111 interface17
interface="interface2"
3021988741 186 interface2
Looks like it is an issue only with bash on cygwin. The script seems to be working just fine on unix
for i in ls interface*; do chksum1=cksum $i | awk -F" " '{ print $1 }'; echo $i, $chksum1; done
interface1, 4294967295
interface2, 4294967295
Try this;
for i in ls interface*; do echo "interface=$i"; chksum1=$(cksum $i | awk -F" " '{ print "'$1'" }'); echo "$chksum1"; done
I like adding the echo statement to verify your getting what you think with the ls statement and the variable assignment should use $(cmd) or `cmd`
Cheers
What you have in your 2nd script:
print "'$1'"
is a completely different statement from what you have in your first one:
print $1
Think about it and ask yourself why you changed it and what it is you're trying to achieve. Also man awk and see g at http://cfajohnson.com/shell/cus-faq-2.html#Q24 for what print "'$1'" does.
Best I can tell without and provided sample input your script should be written:
for i in interface*; do chksum1=$(cksum "$i" | awk '{ print $1 }'); echo "$chksum1"; done
I would like to remove a file name only from the following configuration file.
Configuration File -- test.conf
knowledgebase/arun/test.rf
knowledgebase/arunraj/tester/test.drl
knowledgebase/arunraj2/arun/test/tester.drl
The above file should be read. And removed contents should went to another file called output.txt
Following are my try. It is not working to me at all. I am getting empty files only.
#!/bin/bash
file=test.conf
while IFS= read -r line
do
# grep --exclude=*.drl line
# awk 'BEGIN {getline line ; gsub("*.drl","", line) ; print line}'
# awk '{ gsub("/",".drl",$NF); print line }' arun.conf
# awk 'NF{NF--};1' line arun.conf
echo $line | rev | cut -d'/' -f 1 | rev >> output.txt
done < "$file"
Expected Output :
knowledgebase/arun
knowledgebase/arunraj/tester
knowledgebase/arunraj2/arun/test
There's the dirname command to make it easy and reliable:
#!/bin/bash
file=test.conf
while IFS= read -r line
do
dirname "$line"
done < "$file" > output.txt
There are Bash shell parameter expansions that will work OK with the list of names given but won't work reliably for some names:
file=test.conf
while IFS= read -r line
do
echo "${line%/*}"
done < "$file" > output.txt
There's sed to do the job — easily with the given set of names:
sed 's%/[^/]*$%%' test.conf > output.txt
It's harder if you have to deal with names like /plain.file (or plain.file — the same sorts of edge cases that trip up the shell expansion).
You could add Perl, Python, Awk variants to the list of ways of doing the job.
You can get the path like this:
path=${fullpath%/*}
It cuts away the string after the last /
Using awk one liner you can do this:
awk 'BEGIN{FS=OFS="/"} {NF--} 1' test.conf
Output:
knowledgebase/arun
knowledgebase/arunraj/tester
knowledgebase/arunraj2/arun/test
I have the following script:
#!/bin/bash
…code setting array ids, etc…
for i in "${!ids[#]}" ; do
echo "#${ids[i]}_${pos[i]}_${wild[i]}_${sub[i]}"
curl -sS "http://www.uniprot.org/uniprot/"${ids[i]}".fasta";
done |
sed '/^>/ d' |
sed -r 's/[#]+/>/g' |
perl -npe 'chomp if ($.!=1 && !s/^>/\n>/)' > $id.pph.fasta
However the results will not store in the file. I can output the result to the terminal and store in file by doing:
./myscript > result.txt
However I want to do this within the script and output to file outside the loop.
Add
exec 1>result.txt
to the top of the script, and all output will be redirected.
Here is a variation of your script:
#!/bin/sh
for i in ${!ids[*]}
do
echo ">${ids[i]}_${pos[i]}_${wild[i]}_${sub[i]}"
curl -Ss www.uniprot.org/uniprot/${ids[i]}.fasta
done |
awk '
/>/ {if (z++) printf RS; print; printf RS; getline; next}
1
END {printf RS}
' ORS= > $id.pph.fasta
I have written a script finding the hash value from a dictionary and outputting it in the form "word:md5sum" for each word. I then have a file of names which I would like to use to place each name followed by every hash value i.e.
tom:word1hash
tom:word2hash
.
.
bob:word1hash
and so on. Everything works fine but I can not figure out the substitution. Here is my script.
$#!/bin/bash
#/etc/dictionaries-common/words
cat words.txt | while read line; do echo -n "$line:" >> dbHashFile.txt
echo "$line" | md5sum | sed 's/[ ]-//g' >> dbHashFile.txt; done
cat users.txt | while read name
do
cat dbHashFile.txt >> nameHash.txt;
awk '{$1="$name"}' nameHash.txt;
cat nameHash.txt >> dbHash.txt;
done
the line
$awk '{$1="$name"}' nameHash.txt;
is where I attempt to do the substitution.
thank you for your help
Try replacing the entire contents of the last loop (both cats and the awk) with:
awk -v name="$name" -F ':' '{ print name ":" $2 }' dbHashFile.txt >>dbHash.txt