So in my endless quest for syntactic sugar, I discovered the standard Shell.pm module. This will make my random glue much more readable, thought I. So I tried it out, and it was good; even better when combined with autoquoting arrows (not demonstrated here for clarity). Trouble is, try as I might, I was unable to pass arguments with spaces to the spawned process: they were always seen as two separate arguments, no matter how much I escaped them.

use Shell qw(oggenc);

# ("bar.wav" doesn't exist, so errors of the form "cannot open input f
+ile
# 'bar.wav' indicate the command is being parsed correctly.  "Multiple
+ input
# files" type errors indicate that the spaced argument is being seen a
+s two.)

# All the system() calls work...
# ERROR: Cannot open input file "bar.wav": No such file or directory
system("oggenc -o foo.ogg -c " . quotemeta("composer=J. Random Hacker"
+) .  " bar.wav");
# ERROR: Cannot open input file "bar.wav": No such file or directory
system("oggenc", "-o", "foo.ogg", "-c", "composer=J. Random Hacker", "
+bar.wav");

# None of the Shell.pm ones do.
# ERROR: Multiple input files with specified output filename: suggest 
+using -n
oggenc("-o", "foo.ogg", "-c", "composer=J. Random Hacker", "bar.wav");
# ERROR: Multiple input files with specified output filename: suggest 
+using -n
oggenc("-o", "foo.ogg", "-c", quotemeta("composer=J. Random Hacker"), 
+"bar.wav");
# ERROR: Multiple input files with specified output filename: suggest 
+using -n
oggenc("-o foo.ogg -c " . quotemeta("composer=J. Random Hacker") . " b
+ar.wav");

[download]

Does anyone know how I can pass an argument with whitespace in it? If not, why, and is this to be construed as a bug or a feature? Thanks in advance. (Looking back, I have no idea why the first part of this node is written in the past tense. Nevermind.)

--
amoe

In reply to Shell.pm mangling arguments with embedded whitespace? by Amoe

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