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 ...
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" } 用法示例: $ lines ~/.bashrc 48 $ lines_loop ~/.bashrc 48 计算...
[me@linux ~]$ while : ; do echo "infinite loop"; done infinite loop ... Using a while-loop is generally the recommended way in Bash for iterating over each line of a file or stream. See the FAQ How To Loop Over Each Lines Of A File? for an example. The Until loop...
...在打印文件和目录时,我们根据不同的缩进级别使用printf命令实现缩进效果。最后,我们调用traverse函数并传入待遍历的路径作为参数,即可开始文件系统的遍历。.../bin/bash# 定义一个变量来存储总行数total_lines=0# 设置要统计行数的目录dir="/path/to/directory"# 循环遍历目录下的所有文件for file in $(find...
代码如下:data = file.read(-1)读取文件内容后,我们可以使用 split() 方法来将文件内容分割成行。...代码如下:lines = data.split('\n')现在,我们就可以使用 lines 列表来访问文件中的每一行数据了。...例如,要访问第一行数据,我们可以使用以下代码:line1 = lines[0]要访问第二行数...
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...
head() {# Usage: head "n" "file"mapfile-tn"$1"line <"$2"printf'%s\n'"${line[@]}"} 用法示例: $head2 ~/.bashrc# PromptPS1='➜ '$head1 ~/.bashrc# Prompt 获取文件的最后N行 替代tail命令。 CAVEAT:需要bash4+ 示例功能: ...
In larger scripts, you might need to process large amounts of data stored in arrays. For instance, you might have a script that reads lines from a file into an array and then processes each line individually. In such cases, knowing how to loop through arrays in Bash is invaluable. ...
lineCount=$[$lineCount+$lines] fi done echo "The number of text file is $textCount." echo "The number of line of text file is $lineCount." 控制变量 for语句的控制变量,其实就是类似于C风格的for语句。 for((expr1; expr2; expr3));doBODYdone ...
In larger scripts, ‘foreach’ loops can be used to iterate over arrays or lists of data, process files, and automate repetitive tasks. For instance, you might use a ‘foreach’ loop to process a list of files, perform operations on each file, and generate a report. ...