一、shell流程控制 1、和其他语言不一样,sh 的流程控制不可为空。如果 else 分支没有语句执行,就不要写这个 else。 2、if else 流程 (1)if 语句语法格式: if condition then command1 command2 ... commandN fi 写成一行(
一、shell的if语句 1. if then if 语句语法格式: ifconditionthencommand1 command2...commandNfi 2.if else if else 语法格式: ifconditionthencommand1 command2...commandNelsecommandfi 3.if elif else if else-if else 语法格式: ifcondition1thencommand1elifcondition2thencommand2elsecommandNfi 举例子:...
末尾的fi就是if倒过来拼写,后面还会遇到类似的。 ifelse ifelse语法格式: ifcondition then command1 command2 ... commandN else command fi 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. if else-if else 语法格式: ifcondition1 then command1 elifcondition2 then command2 else commandN fi 1...
11. Shell 赋值 i=$((c/1000)); 赋值语句前后不能有空格 12. Shell 多进程 for ((i=0;i<5;i++));do } & & shell 13. 执行语句后面加上 2>/dev/null 就可以清楚系统的输出信息 如: Curl www.baidu.com 2>/dev/null 这样就不会输出提示信息了 14. Shell 创建文件夹 mkdir ...
forloopin12345doecho"The value is: $loop"done if else if 语句语法格式: 代码语言:javascript 复制 ifcondition then command1 command2...commandN fi 写成一行(适用于终端命令提示符): 代码语言:javascript 复制 if[$(ps-ef|grep-c"ssh")-gt1];then echo"true";fi ...
best of 3: 0.0748 usec per loop $ python -mtimeit -s'x=1' 'if x: d=1' 'else: d=...
I inside first loop: 0 I inside first loop: 1 I inside first loop: 2 I inside first loop: 3 I inside first loop: 4 I inside first loop: 5 I inside first loop: 6 I inside first loop: 7 I inside first loop: 8 I inside first loop: 9 ---2--- ---3--- Start ...
I inside first loop: 0 I inside first loop: 1 I inside first loop: 2 I inside first loop: 3 I inside first loop: 4 I inside first loop: 5 I inside first loop: 6 I inside first loop: 7 I inside first loop: 8 I inside first loop: 9 ---2--- ---3--- Start I inside ...
nil for unbuffered, 0 for line buffered, anything else for a buffer of that amount. default value: 0 _long_sep: use: This is the character(s) that separate a program’s long argument’s key from the value. default value: "=" _long_prefix: use: This is the character(s) that ...
else { printf("WAY OFF!!!\n"); exit(1); } return 0; } 留住shell cat <(python -c 'print "\xde\xad\xbe\xef"[::-1]*6') - | ./narnia0 GG (python -c 'print "\xde\xad\xbe\xef"[::-1]*6'; cat) | ./narnia0 Correct val's value from 0x41414141 -> 0xdeadbeef! Her...