| <span style="line-height:normal;"><span style="line-height:22px;font-size:14px;color:rgb(255,255,255);">运算符</span></span> | <span style="line-height:normal;"><span style="line-height:22px;font-size:14px;color:rgb(255,255,255);">描述</span></span> | <span style="line-height:normal;"><span style="line-height:22px;font-size:14px;color:rgb(255,255,255);">示例</span></span> |
| <span style="line-height:normal;"><span style="line-height:22px;font-size:14px;color:rgb(255,255,0);">文件比较运算符</span></span> |
| <span style="line-height:normal;font-size:14px;">-e </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">filename</span></span> | <span style="line-height:normal;font-size:14px;">如果 </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">filename</span></span><span style="line-height:normal;font-size:14px;"> 存在，则为真</span> | <span style="line-height:normal;font-size:14px;">[ -e /var/log/syslog ]</span> |
| <span style="line-height:normal;font-size:14px;">-d </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">filename</span></span> | <span style="line-height:normal;font-size:14px;">如果 </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">filename</span></span><span style="line-height:normal;font-size:14px;"> 为目录，则为真</span> | <span style="line-height:normal;font-size:14px;">[ -d /tmp/mydir ]</span> |
| <span style="line-height:normal;font-size:14px;">-f </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">filename</span></span> | <span style="line-height:normal;font-size:14px;">如果 </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">filename</span></span><span style="line-height:normal;font-size:14px;"> 为常规文件，则为真</span> | <span style="line-height:normal;font-size:14px;">[ -f /usr/bin/grep ]</span> |
| <span style="line-height:normal;font-size:14px;">-L </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">filename</span></span> | <span style="line-height:normal;font-size:14px;">如果 </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">filename</span></span><span style="line-height:normal;font-size:14px;"> 为符号链接，则为真</span> | <span style="line-height:normal;font-size:14px;">[ -L /usr/bin/grep ]</span> |
| <span style="line-height:normal;font-size:14px;">-r </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">filename</span></span> | <span style="line-height:normal;font-size:14px;">如果 </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">filename</span></span><span style="line-height:normal;font-size:14px;"> 可读，则为真</span> | <span style="line-height:normal;font-size:14px;">[ -r /var/log/syslog ]</span> |
| <span style="line-height:normal;font-size:14px;">-w </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">filename</span></span> | <span style="line-height:normal;font-size:14px;">如果 </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">filename</span></span><span style="line-height:normal;font-size:14px;"> 可写，则为真</span> | <span style="line-height:normal;font-size:14px;">[ -w /var/mytmp.txt ]</span> |
| <span style="line-height:normal;font-size:14px;">-x </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">filename</span></span> | <span style="line-height:normal;font-size:14px;">如果 </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">filename</span></span><span style="line-height:normal;font-size:14px;"> 可执行，则为真</span> | <span style="line-height:normal;font-size:14px;">[ -L /usr/bin/grep ]</span> |
| <span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">filename1</span></span><span style="line-height:normal;font-size:14px;"> -nt </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">filename2</span></span> | <span style="line-height:normal;font-size:14px;">如果 </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">filename1</span></span><span style="line-height:normal;font-size:14px;"> 比 </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">filename2</span></span><span style="line-height:normal;font-size:14px;"> 新，则为真</span> | <span style="line-height:normal;font-size:14px;">[ /tmp/install/etc/services -nt /etc/services ]</span> |
| <span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">filename1</span></span><span style="line-height:normal;font-size:14px;"> -ot </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">filename2</span></span> | <span style="line-height:normal;font-size:14px;">如果 </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">filename1</span></span><span style="line-height:normal;font-size:14px;"> 比 </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">filename2</span></span><span style="line-height:normal;font-size:14px;"> 旧，则为真</span> | <span style="line-height:normal;font-size:14px;">[ /boot/bzImage -ot arch/i386/boot/bzImage ]</span> |
| <span style="line-height:normal;"><span style="line-height:22px;font-size:14px;color:rgb(255,255,0);">字符串比较运算符</span></span><span style="line-height:normal;font-size:14px;color:rgb(255,255,0);"> </span><span style="line-height:20px;font-size:14px;color:rgb(255,255,255);">（请注意引号的使用，这是防止空格扰乱代码的好方法）</span> |
| <span style="line-height:normal;font-size:14px;">-z </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">string</span></span> | <span style="line-height:normal;font-size:14px;">如果 </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">string</span></span><span style="line-height:normal;font-size:14px;"> 长度为零，则为真</span> | <span style="line-height:normal;font-size:14px;">[ -z "$myvar" ]</span></td></tr><tr style="line-height:normal;"><td style="font-family:Arial;visibility:visible !important;line-height:22px;"><span style="line-height:normal;font-size:14px;">-n </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">string</span></span></td><td style="font-family:Arial;visibility:visible !important;line-height:22px;"><span style="line-height:normal;font-size:14px;">如果 </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">string</span></span><span style="line-height:normal;font-size:14px;"> 长度非零，则为真</span></td><td style="font-family:Arial;visibility:visible !important;line-height:22px;"><span style="line-height:normal;font-size:14px;">[ -n "$myvar" ]</span> |
| <span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">string1</span></span><span style="line-height:normal;font-size:14px;"> = </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">string2</span></span> | <span style="line-height:normal;font-size:14px;">如果 </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">string1</span></span><span style="line-height:normal;font-size:14px;"> 与 </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">string2</span></span><span style="line-height:normal;font-size:14px;"> 相同，则为真</span> | <span style="line-height:normal;font-size:14px;">[ "$myvar" = "one two three" ]</span></td></tr><tr style="line-height:normal;"><td style="font-family:Arial;visibility:visible !important;line-height:22px;"><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">string1</span></span><span style="line-height:normal;font-size:14px;"> != </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">string2</span></span></td><td style="font-family:Arial;visibility:visible !important;line-height:22px;"><span style="line-height:normal;font-size:14px;">如果 </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">string1</span></span><span style="line-height:normal;font-size:14px;"> 与 </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">string2</span></span><span style="line-height:normal;font-size:14px;"> 不同，则为真</span></td><td style="font-family:Arial;visibility:visible !important;line-height:22px;"><span style="line-height:normal;font-size:14px;">[ "$myvar" != "one two three" ]</span> |
| <span style="line-height:normal;"><span style="line-height:22px;font-size:14px;color:rgb(255,255,0);">算术比较运算符</span></span> |
| <span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">num1</span></span><span style="line-height:normal;font-size:14px;"> -eq </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">num2</span></span> | <span style="line-height:normal;font-size:14px;">等于</span> | <span style="line-height:normal;font-size:14px;">[ 3 -eq $mynum ]</span></td></tr><tr style="line-height:normal;"><td style="font-family:Arial;visibility:visible !important;line-height:22px;"><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">num1</span></span><span style="line-height:normal;font-size:14px;"> -ne </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">num2</span></span></td><td style="font-family:Arial;visibility:visible !important;line-height:22px;"><span style="line-height:normal;font-size:14px;">不等于</span></td><td style="font-family:Arial;visibility:visible !important;line-height:22px;"><span style="line-height:normal;font-size:14px;">[ 3 -ne $mynum ]</span> |
| <span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">num1</span></span><span style="line-height:normal;font-size:14px;"> -lt </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">num2</span></span> | <span style="line-height:normal;font-size:14px;">小于</span> | <span style="line-height:normal;font-size:14px;">[ 3 -lt $mynum ]</span></td></tr><tr style="line-height:normal;"><td style="font-family:Arial;visibility:visible !important;line-height:22px;"><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">num1</span></span><span style="line-height:normal;font-size:14px;"> -le </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">num2</span></span></td><td style="font-family:Arial;visibility:visible !important;line-height:22px;"><span style="line-height:normal;font-size:14px;">小于或等于</span></td><td style="font-family:Arial;visibility:visible !important;line-height:22px;"><span style="line-height:normal;font-size:14px;">[ 3 -le $mynum ]</span> |
| <span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">num1</span></span><span style="line-height:normal;font-size:14px;"> -gt </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">num2</span></span> | <span style="line-height:normal;font-size:14px;">大于</span> | <span style="line-height:normal;font-size:14px;">[ 3 -gt $mynum ]</span></td></tr><tr style="line-height:normal;"><td style="font-family:Arial;visibility:visible !important;line-height:22px;"><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">num1</span></span><span style="line-height:normal;font-size:14px;"> -ge </span><span style="line-height:normal;"><span style="line-height:normal;font-size:14px;">num2</span></span></td><td style="font-family:Arial;visibility:visible !important;line-height:22px;"><span style="line-height:normal;font-size:14px;">大于或等于</span></td><td style="font-family:Arial;visibility:visible !important;line-height:22px;"><span style="line-height:normal;font-size:14px;">[ 3 -ge $mynum ]</span>
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