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