Otherwise, the test command returns a non-zero value. This works great with the if command. In fact, there's an alias to the test command. Try this: $ ls -li /bin/test /bin/[ The i prints out the inode. The inode is the real ID of the file. Files with the same ID are ...
Following http://www.cyberciti.biz/tips/find-out-if-file-exists-with-conditional-expressions.html, I've tried the following: [-e archived_sensor_data.json] && rm archived_sensor_data.json However, this throws an error [-e: command not found when I try to run the resulting test_contr...
How To Check If A Folder Exists With PowerShell You can use something like this for verification on the command line: PS C:\> Test-Path C:\Windows True Remember that you need single or double quotes around the path if it contains a space. Single quotes are recommended, since they don'...
if[ -z$CURRENT_HOUR];thenecho"CURRENT_HOUR parameter is empty."echo"usage : sh$0A|B Config Cur_Hour"exit1fiif[ $? -eq 0 -a -s${tmp_file}];thenrsync -aP${tmp_file}${zabbix_file}else/opt/monitor/sendsms.sh"zabbix Connection to the platform database(machine) failed""songwanbo"ex...
A "tail -f" equivalent command in Powershell to show real time logging A call to SSPI failed A connection to the directory on which to process the request was unavailable. This is likely a transient condition. A fast way to remove duplicated lines from an unsorted text file? a lot of ...
# Check the existence of jstack command!if ! which jstack &> /dev/null; then[ -z "$JAVA_HOME" ] && {redEcho "Error: jstack not found on PATH!"exit 1}! [ -f "$JAVA_HOME/bin/jstack" ] && {redEcho "Error: jstack not found on PATH and $JAVA_HOME/bin/jstack file does NOT ...
# Check the existence of jstack command! if ! which jstack &> /dev/null; then [ -z "$JAVA_HOME" ] && { redEcho "Error: jstack not found on PATH!" exit 1 } ! [ -f "$JAVA_HOME/bin/jstack" ] && { redEcho "Error: jstack not found on PATH and $JAVA_HOME/bin/jstack file...
true 永远返回成功结果 : null command ,什么也不干,返回成功结果 false 永远返回错误结果创建无限循环 while true ;do 循环体 done 4、循环中可并行执行,使脚本运行更快 1)用法 for name in 列表 ;do { 循环体 }& done wait 2)实例: #搜寻自己指定ip(子网掩码为24的)的网段中,UP的ip地址 read ...
-Path: This parameter indicates the path to the folder or file you want to check for existence. In this case, it’s set to "C:\Path\to\Folder", indicating that you want to check if the folder located on that path exists. For example, the following command checks whether all elements...
if grep $testuser /etc/passwd then echo The bash files foruser $testuser are : ls -a /home/$testuser/.b* fi 注意:在一些脚本中,可能会看到 if-then 语句的另一种形式: if command; then commands fi 在计值的命令末尾使用一个分号,可以将 then 语句包含在此行中,这更像是在其他一些编程语言...