gawk: Obsolete

1 
1 2.9 Obsolete Options and/or Features
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1 
1 This minor node describes features and/or command-line options from
1 previous releases of 'gawk' that either are not available in the current
1 version or are still supported but deprecated (meaning that they will
1 _not_ be in the next release).
1 
1    The process-related special files '/dev/pid', '/dev/ppid',
1 '/dev/pgrpid', and '/dev/user' were deprecated in 'gawk' 3.1, but still
1 worked.  As of version 4.0, they are no longer interpreted specially by
1 'gawk'.  (Use 'PROCINFO' instead; see ⇒Auto-set.)
1