* THE STATUS OF GNU SED It has long been noted that GNU sed is much slower than other implementations. The current bottleneck is the way sed reads and writes data files. It should read large blocks at a time (or even map files, where that is supported). When possible, it should avoid copying it's input from one place in memory to another. Patches to make it do those things are welcome! * ABOUT BUGS Before reporting a bug, please check the list of oft-reported non-bugs (below). Bugs and comments may be sent to bug-gnu-utils@prep.ai.mit.edu. Please do not send a bug report like this: [while building frobme-1.3.4] $ configure sed: file sedscr line 1: Unknown option to 's' $ sed --version GNU sed version 2.04 If GNU sed doesn't configure your favorite package, take a few extra minutes to identify the specific problem and make a stand-alone test case. A stand-alone test case includes all the data necessary to perform the test, and the specific invocation of sed that causes the problem. The smaller a stand-alone test case is, the better. A test case should not involve something as far removed from sed as ``try to configure frobme-1.3.2''. Yes, that is in principle enough information to look for the bug, but that is not a very practical prospect. & NONBUGS `sed -n' and `s/regex/replace/p' Some versions of sed ignore the `p' (print) option of an `s' command unless the `-n' command switch has been specified. Other versions always honor the `p' option. GNU sed is the latter sort. regexp syntax clashes GNU sed uses the Posix basic regular expression syntax. According to the standard, the meaning of some escape sequences is undefined in this syntax; notably `\|' and `\+'. As in all GNU programs that use Posix basic regular expressions, sed interprets these escape sequences as meta-characters. So, `x\+' matches one or more occurences of `x'. `abc\|def' matches either `abc' or `def'. This syntax may cause problems when running scripts written for other seds. Some sed programs have been written with the assumption that `\|' and `\+' match the literal characters `|' and `+'. Such scripts must be modified by removing the spurious backslashes if they are to be used with GNU sed. [If you have need of a free sed that understands the regexp syntax of your choice, the source to GNU sed may be a good place to start. Consider changing the call to re_set_syntax in function main in `sed.c'. The file regex.h contains an explanation of the supported syntax options.]
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.
