$3 $3" # 访问传入的参数 echo "the number of parameters: \$# $#" # 传入的参数数量 echo "all parameters: \$@ $@" # 每个参数作为独立字符串 echo "all parameters: \$* $*" # 所有参数合在一个字符串中 pwd # linux 打印当前路径的命令 echo "exit status of the previous command: \$?
So we want to prepend sudo to the previous command. Of course, we can press Ctrl-p to recall the last command, move the cursor to the right position, and type sudo. Well, “sudo” is short, and moving the cursor (pressing Ctrl-a) to the very beginning isn’t hard to do. However...
echo "This is a new line." >> temp.txt: Appends the specified line to the file "output.txt". if [ $? -eq 0 ]; then: Checks the exit status of the previous command. If it's 0 (indicating success), print a success message. Otherwise, it prints a failure message. 9. Write a ...
if [ $? -eq 0 ]; then ... else ... fi: This construct checks the exit status of the previous command. If the exit status is 0 (indicating success), it prints the message "Files compressed successfully into 'compressed_files.tar.gz'." Otherwise, it prints "Failed to compress files ...
Bash's exit status is the exit status of the last command executed in the script. If no commands are executed, the exit status is 0. An attempt is first made to open the file in the current directory, and, if no file is found, then the shell searches the directories in PATH for ...
local status=$? # Test the exit status of the command run # and display an error message on failure if test ${status} -ne 0 then echo Command ""$@"" failed >&2 fi return ${status} }通过在要运行的命令的名称中附加0或最后一个返回值来调用它,这样就可以在不检查错误值的情况下链接命令...
spec 替换为相应的进程组ID,执行 command,传递参数 args 给它并返 回它的退出状态。 kill [-s sigspec | -n signum | -sigspec] [pid | jobspec] ... kill -l [sigspec | exit_status] 向以 pid 或 jobspec 为名的进程发送名为 sigspec 或 signum 的信 号 。 sigspec 可以是一个信号名称,类似 ...
Sincefalsehas an exit status of 1, the programecho "Program 2 was executed."is not executed, so nothing is printed to the console for that command. Several AND operators can be chained together like so: false&&true&&echoHelloecho1&&false&&echo3echoAthos&&echoPorthos&&echoAramis ...
$ curl -fSsL "https://raw.githubusercontent.com/imomaliev/tmux-bash-completion/master/completions/tmux" > "${dir?error: dir not set: you must run the previous commands first}/tmux" Reload your configuration files $ source ~/.bashrc Without bash-completion You can simply download the compl...
Run the script using the following command: $ bash set1.bash Read the values of the variable using the “echo” command: $ echo $v1 $v2 $v3 The following output appears after executing the previous commands: Example 2: Using the Set Command with -C Option ...