此方法使用的内存少于mapfile方法,并在bash3中工作,但对于较大的文件,它的速度较慢。 lines_loop() { # Usage: lines_loop "file" count=0 while IFS= read -r _; do ((count++)) done < "$1" printf '%s\n' "$count" } 1. 2. 3. 4. 5. 6. 7. 8. 用法示例: $ lines ~/.bashrc ...
# Loop from 0-VAR. VAR=50 for ((i=0;i<=VAR;i++)); do printf '%s\n' "$i" done 循环数组 arr=(apples oranges tomatoes) # Just elements. for element in "${arr[@]}"; do printf '%s\n' "$element" done 循环遍历带索引的数组 arr=(apples oranges tomatoes) # Elements and index...
break 2 ## break out of both while and for loops elif [ $RANDOM -lt 10000 ] then printf '"' break ## break out of the while loop fi done done echo 继续 在循环内部, continue命令通过传递任何剩余命令,立即开始循环的新迭代: for n in {1..9} ## See Brace expansion in Chapter 4 d...
"exit1fideclare-i textCount=0declare-i lineCount=0foriin$1/*; do if [ -f $i ]; then lines=$(wc -l $i | cut -d " " -f 1) textCount=$[$textCount+1] lineCount=$[$lineCount+$lines] fi done echo "The number of text file is $textCount." echo "The number of line of...
How to do a foreach loop in bash? How to do a do-while loop in bash? How to create an infinite loop in bash? How to find if a number is odd or even in bash? How to iterate over a bash array? How to loop over each line of a file? How to iterate over a list of files?
awk 'FRN == RN {wordsArr[++wordsCount] = $0} # read file1 lines into array FRN != RN && /example/ { # read file2 line matching regExp /example/ for (i in wordsArr) { # scan all words in array if ($0 ~ wordsArr[i]) { # if a word matched in current line print; # ...
done < file.txt echo "Total number of lines are $i" Looking at the Number of Items in a Directory using Bash while Loop The counters are a crucial part of bash scripting especially to control the iterations. The example of counting the number of lines or the number of items in a direc...
Open up you favorite text editor and a create file called hello_world.sh. Insert the following lines to a file: NOTE:Every bash shell script in this tutorial starts withshebang:"#!"which is not read as a comment. First line is also a place where you put your interpreter which is in...
In this example, we’ve created a ‘for’ loop that acts as a ‘foreach’ loop. The loop iterates over the numbers 1 through 5, echoing each number on a new line. This is a basic way to use the ‘foreach’ loop in Bash, but there’s much more to learn about looping and itera...
What is a one-line for loop in Bash? How many times does a for loop run in Bash? How to iterate on multiple lines in a for loop in bash? Solution 1: Ensure that there are no spaces following the backslash. for i in foo_dir/foo_filename.xml,passed,"some string" \ ...