57 lines
1.3 KiB
Python
57 lines
1.3 KiB
Python
# Module 'commands'
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#
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# Various tools for executing commands and looking at their output and status.
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#
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# NB This only works (and is only relevant) for UNIX.
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# Get 'ls -l' status for an object into a string
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#
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def getstatus(file):
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return getoutput('ls -ld' + mkarg(file))
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# Get the output from a shell command into a string.
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# The exit status is ignored; a trailing newline is stripped.
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# Assume the command will work with '{ ... ; } 2>&1' around it..
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#
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def getoutput(cmd):
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return getstatusoutput(cmd)[1]
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# Ditto but preserving the exit status.
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# Returns a pair (sts, output)
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#
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def getstatusoutput(cmd):
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import posix
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pipe = posix.popen('{ ' + cmd + '; } 2>&1', 'r')
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text = pipe.read()
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sts = pipe.close()
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if sts == None: sts = 0
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if text[-1:] == '\n': text = text[:-1]
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return sts, text
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# Make command argument from directory and pathname (prefix space, add quotes).
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#
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def mk2arg(head, x):
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import posixpath
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return mkarg(posixpath.join(head, x))
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# Make a shell command argument from a string.
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# Two strategies: enclose in single quotes if it contains none;
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# otherwise, enclose in double quotes and prefix quotable characters
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# with backslash.
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#
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def mkarg(x):
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if '\'' not in x:
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return ' \'' + x + '\''
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s = ' "'
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for c in x:
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if c in '\\$"':
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s = s + '\\'
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s = s + c
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s = s + '"'
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return s
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