当我们在应用Python编程语言进行程序开发的时候,我们会发现这一语言可以帮助我们轻松的完成一些特定的功能需求。在这里我们就先一起来了解一下Python调用zip命令的使用方法,以此了解这一语言的操作方法。
Python调用zip命令例子程序是这样的:
- #!/usr/bin/Python
- # Filename: backup_ver1.py
- import os
- import time
- # 1. The files and directories to be backed up are specified in a list.
- source = ['/home/swaroop/byte', '/home/swaroop/bin']
- # If you are using Windows, use source = [r'C:\Documents', r'D:\Work']
or something like that- # 2. The backup must be stored in a main backup directory
- target_dir = '/mnt/e/backup/' # Remember to change this to what
you will be using- # 3. The files are backed up into a zip file.
- # 4. The name of the zip archive is the current date and time
- target = target_dir + time.strftime('%Y%m%d%H%M%S') + '.zip'
- # 5. We use the zip command (in Unix/Linux) to put the files
in a zip archive- zip_command = "zip -qr '%s' %s" % (target, ' '.join(source))
- # Run the backup
- if os.system(zip_command) == 0:
- print 'Successful backup to', target
- else:
- print 'Backup FAILED'
由于上面Python调用zip命令例子是在Unix/Linux下的,需要改成windows
- #!/usr/bin/Python
- # Filename: backup_ver1.py
- import os
- import time
- source =[r'C:\My Documents', r'D:\Work']
- target_dir = r'F:\back up\' # Remember to change this to
what you will be using- target = target_dir + time.strftime('%Y%m%d%H%M%S') + '.zip'
- zip_command = "zip -qr '%s' %s" % (target, ' '.join(source))
- # Run the backup
- if os.system(zip_command) == 0:
- print 'Successful backup to', target
- else:
- print 'Backup FAILED'
问题一:
当改好后,运行会发生异常,提示:"EOL while scanning single-quoted string",该异常出现在上面代码的粗体行
- target_dir = r'F:\back up\'
在Python调用zip命令中,发生错误主要是因为转义符与自然符号串间的问题,看Python的介绍:#t#
自然字符串
如果你想要指示某些不需要如转义符那样的特别处理的字符串,那么你需要指定一个自然字符串。自然字符串通过给字符串加上前缀r或R来指定。例如r"Newlines are indicated by /n"。
如上所说, target_dir的值应该被视作 'F:\back up\',可是这里的转义符却被处理了。如果换成 r'F:\\back up\\' 转义符却没被处理,于是target_dir的值变为'F:\\back up\\'.将单引号变成双引号,结果还是如此。而如果给它加中括号【】,变成【r'F:\back up\'】,则程序又没问题...
于是,解决方法有2个:1)如上所说,加中括号;2)不使用前缀r,直接用转义符‘\’,定义变成target_dir = 'F:\\back up\\'.
问题二:
解决完问题一后,运行module,会提示backup fail. 检查如下:
1. 于是试着将source和target字符串打印出来检验是否文件路径出错,发现没问题
2. 怀疑是windows没有zip命令,在命令行里打‘zip’, 却出现提示帮助,证明可以用zip命令,而且有参数q,r;
3. 想起sqlplus里命令不接受空格符,于是试着将文件名换成没空格的, module成功运行...
现在问题换成如何能让zip命令接受带空格路径,google了一下,看到提示:“带有空格的通配符或文件名必须加上引号”
于是对 zip_command稍做修改,将
zip_command = "zip -qr '%s' %s" % (target, ' '.join(source))
改成:
zip_command = "zip -qr \"%s\" \"%s\"" % (target, '\" \"'.join(source))
改后,module成功运行...
正确的script应为:
- #!/usr/bin/Python
- # Filename: backup_ver1.py
- import os
- import time
- source =[r'C:\My Documents', r'D:\Work']
- target_dir = 'F:\\back up\\' # Remember to change this to what
you will be using- target = target_dir + time.strftime('%Y%m%d%H%M%S') + '.zip'
- zip_command = "zip -qr \"%s\" \"%s\"" % (target, ' '.join(source))
- # Run the backup
- if os.system(zip_command) == 0:
- print 'Successful backup to', target
- else:
- print 'Backup FAILED'
以上就是我们对Python调用zip命令的相关介绍。