babbage% gcc -o read-write-4 read-write-4.c && read-write-4 
The writer process 1 begins.
The writer process 2 begins.
The writer process 4 begins.
The writer process 3 begins.
The writer process 5 begins.
The writer process 6 begins.
The reader process 2 begins.
Reader 2: item  0 == 100
Reader 2: item  1 == 101
Reader 2: item  2 == 102
Reader 2: item  3 == 103
The reader process 1 begins.
Reader 1: item  0 == 104
Reader 1: item  1 == 105
Reader 1: item  2 == 200
Reader 1: item  3 == 400
Reader 1: item  4 == 300
The reader process 3 begins.
Reader 3: item  0 == 500
Reader 3: item  1 == 600
Reader 3: item  2 == 106
The reader process 4 begins.
Reader 4: item  0 == 201
Reader 4: item  1 == 401
The reader process 5 begins.
Reader 5: item  0 == 301
All child processes spawned by parent
Parent waiting for children to finish
Reader 2: item  4 == 501
Reader 1: item  5 == 601
Reader 1: item  6 == 107
Reader 1: item  7 == 202
Reader 1: item  8 == 402
Reader 1: item  9 == 302
Reader 4: item  2 == 602
Reader 4: item  3 == 108
Writer 1 done.
Reader 4: item  4 == 203
Reader 4: item  5 == 403
Reader 3: item  3 == 502
Reader 3: item  4 == 503
Reader 3: item  5 == 603
Reader 3: item  6 == 109
Reader 3: item  7 == 204
Reader 4: item  6 == 303
Reader 5: item  1 == 404
Reader 5: item  2 == 405
Reader 5: item  3 == 504
Reader 5: item  4 == 604
Reader 5: item  5 == 205
Reader 2: item  5 == 406
Reader 2: item  6 == 304
Reader 2: item  7 == 505
Reader 2: item  8 == 605
Reader 1: item 10 == 206
Reader 4: item  7 == 305
Reader 4: item  8 == 506
Reader 4: item  9 == 606
Reader 4: item 10 == 207
Writer 4 done.
Reader 4: item 11 == 408
Reader 3: item  8 == 407
Reader 3: item  9 == 306
Reader 3: item 10 == 507
Reader 3: item 11 == 607
Reader 3 done.
Writer 2 done.
Reader 5: item  6 == 208
Reader 5: item  7 == 409
Writer 5 done.
Reader 5: item  8 == 307
Writer 6 done.
Reader 5: item  9 == 508
Writer 3 done.
Reader 5: item 10 == 608
Reader 2: item  9 == 209
Reader 2: item 10 == 308
Reader 2: item 11 == 509
Reader 2 done.
Reader 1: item 11 == 609
Reader 1 done.
Reader 4 done.
Reader 5: item 11 == 309
Reader 5 done.
Semaphore cleanup complete.