Can someone explain me what does the following script?
#!/bin/bash
for F in *.txt; do
K=`grep abc $F`
echo $K
if ["$K" != ""]; then
echo $F
fi
done
I tested it and when it finds a txt file that contains the "abc" string, on prompt appears
`"./a.sh: line 5: [abc: command not found"`
error, otherwise appears the name of txt file that doesn't contain the "abc" string.
You're getting [abc: command not found because you don't have space after [ and before ] in your if condition.
You don't even need a for loop, you can use grep -l:
grep -l 'abc' *.txt
The script is supposed to iterate over all ".txt" files in the current directory, grep them for abc, echo the result, and if the string was found, print the file name. However, it has a syntax error (you need spaces around [ and ]), breaks on file names with whitespace and is also more complex than needed. A better version is:
#!/bin/bash
for F in *.txt; do
grep abc "$F" && echo "$F"
done
Leave a space after [ and a space before ] to resolve the errors:
#!/bin/bash
for F in *.txt; do
K=`grep abc $F`
echo $K
if [ "$K" != "" ]; then
echo $F
fi
done
Your script goes through all the .txt files in the current directory to search for a pattern and displays the file name where it is matched. Refer to this tutorial http://www.tutorialspoint.com/unix_commands/grep.htm
Your code has a syntax error here
if ["$K" != ""]
You need to put a space after [ and before ] hence use this
if [ "$K" != "" ]
