[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...
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...
This method uses less memory than the mapfile method and works in bash 3 but it is slower for bigger files.lines_loop() { # Usage: lines_loop "file" count=0 while IFS= read -r _; do ((count++)) done < "$1" printf '%s\n' "$count" }...
Loop over files and directoriesFILE HANDLING Read a file to a string Read a file to an array (by line) Get the first N lines of a file Get the last N lines of a file Get the number of lines in a file Count files or directories in directory Create an empty file Extract lines bet...
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. ...
Instead of using theforloop above, I can install theprenamecommand and accomplish the above goal like this: $>prename-v's/.txt/.log/'*.txt file10.txt ->file10.log file1.txt ->file1.log file2.txt ->file2.log file3.txt ->file3.log ...
whileread-r line;doprintf'%s\n'"$line"done<"file" 循环遍历文件和目录 不要用ls。 # Greedy example.forfilein*;doprintf'%s\n'"$file"done# PNG files in dir.forfilein~/Pictures/*.png;doprintf'%s\n'"$file"done# Iterate over directories.fordirin~/Downloads/*/;doprintf'%s\n'"$dir"...
# File: math.sh You do not need to add these lines to your file, though you should type exactly what I have typed below these lines.Note: please type all of the lines out for every program that we’re going to write, do not copy and paste. Typing code is a little different from...
grep'*foo*'file# Globs in regex contextsfind . -execfoo {} && bar {} \;# Prematurely terminated find -execsudoecho'Var=42'> /etc/profile# Redirecting sudotime --format=%s sleep 10# Passing time(1) flags to time builtinwhilereadh;dossh"$h"uptime# Commands eating while loop inputali...