$! being 1 is probably just a default value. I get $! to be 1 as well, but it means something differently: 
  DB<1> x $?, $!                                                      
+          
0  0
1  'Illegal seek'

[download]
However, my pwd does succeed. It still leaves $! to be 1, but it's string value changes: 
  DB<2> x qx|pwd|                                                     
+          
0  '/tmp
'
  DB<3> x $?, $!                                                      
+          
0  0
1  ''

[download]
It's curious to see your pwd fails. Is that from a debugging session where you aren't doing anything else? What happens if you use the fully qualified name to pwd? Anyway, the external pwd failing isn't something that happens on the perl level.

In reply to Re^3: backticks and 'Cannot allocate memory' by JavaFan
in thread backticks and 'Cannot allocate memory' by NetWallah

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