NEWS revision 94
11541SrgrimesVersion 2.0: 21541Srgrimes 31541SrgrimesThe most important user visible change is that egrep and fgrep have 41541Srgrimesdisappeared as separate programs into the single grep program mandated 51541Srgrimesby POSIX 1003.2. New options -G, -E, and -F have been added, 61541Srgrimesselecting grep, egrep, and fgrep behavior respectively. For 71541Srgrimescompatibility with historical practice, hard links named egrep and 81541Srgrimesfgrep are also provided. See the manual page for details. 91541Srgrimes 101541SrgrimesIn addition, the regular expression facilities described in Posix 111541Srgrimesdraft 11.2 are now supported, except for internationalization features 121541Srgrimesrelated to locale-dependent collating sequence information. 131541Srgrimes 141541SrgrimesThere is a new option, -L, which is like -l except it lists 151541Srgrimesfiles which don't contain matches. The reason this option was 161541Srgrimesadded is because '-l -v' doesn't do what you expect. 171541Srgrimes 181541SrgrimesPerformance has been improved; the amount of improvement is platform 191541Srgrimesdependent, but (for example) grep 2.0 typically runs at least 30% faster 201541Srgrimesthan grep 1.6 on a DECstation using the MIPS compiler. Where possible, 211541Srgrimesgrep now uses mmap() for file input; on a Sun 4 running SunOS 4.1 this 221541Srgrimesmay cut system time by as much as half, for a total reduction in running 231541Srgrimestime by nearly 50%. On machines that don't use mmap(), the buffering 241541Srgrimescode has been rewritten to choose more favorable alignments and buffer 251541Srgrimessizes for read(). 261541Srgrimes 271541SrgrimesPortability has been substantially cleaned up, and an automatic 281541Srgrimesconfigure script is now provided. 291541Srgrimes 301541SrgrimesThe internals have changed in ways too numerous to mention. 311541SrgrimesPeople brave enough to reuse the DFA matcher in other programs 321541Srgrimeswill now have their bravery amply "rewarded", for the interface 331541Srgrimesto that file has been completely changed. Some changes were 3450477Speternecessary to track the evolution of the regex package, and since 351541SrgrimesI was changing it anyway I decided to do a general cleanup. 361541Srgrimes