tar: move vfork into separate function (smaller code)
open_transformer: more informative error messages

function                                             old     new   delta
vfork_compressor                                       -     210    +210
writeTarFile                                         547     299    -248
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(add/remove: 1/0 grow/shrink: 0/1 up/down: 210/-248)          Total: -38 bytes

3 files changed