"""Execute shell commands via os.popen() and return status, output.
outtext = commands.getoutput(cmd)
(exitstatus, outtext) = commands.getstatusoutput(cmd)
outtext = commands.getstatus(file) # returns output of "ls -ld file"
A trailing newline is removed from the output string.
Encapsulates the basic operation:
pipe = os.popen('{ ' + cmd + '; } 2>&1', 'r')
[Note: it would be nice to add functions to interpret the exit status.]
__all__
= ["getstatusoutput","getoutput","getstatus"]
# Various tools for executing commands and looking at their output and status.
# NB This only works (and is only relevant) for UNIX.
# Get 'ls -l' status for an object into a string
"""Return output of "ls -ld <file>" in a string."""
return getoutput('ls -ld' + mkarg(file))
# Get the output from a shell command into a string.
# The exit status is ignored; a trailing newline is stripped.
# Assume the command will work with '{ ... ; } 2>&1' around it..
"""Return output (stdout or stderr) of executing cmd in a shell."""
return getstatusoutput(cmd
)[1]
# Ditto but preserving the exit status.
# Returns a pair (sts, output)
def getstatusoutput(cmd
):
"""Return (status, output) of executing cmd in a shell."""
pipe
= os
.popen('{ ' + cmd
+ '; } 2>&1', 'r')
if text
[-1:] == '\n': text
= text
[:-1]
# Make command argument from directory and pathname (prefix space, add quotes).
return mkarg(os
.path
.join(head
, x
))
# Make a shell command argument from a string.
# Return a string beginning with a space followed by a shell-quoted
# version of the argument.
# Two strategies: enclose in single quotes if it contains none;
# otherwise, enclose in double quotes and prefix quotable characters