HTTP/2 302 server: nginx date: Wed, 16 Jul 2025 05:43:12 GMT content-type: text/plain; charset=utf-8 content-length: 0 x-archive-redirect-reason: found capture at 20090210084109 location: https://web.archive.org/web/20090210084109/https://examples.oreilly.com/upt2/split/look.shar server-timing: captures_list;dur=0.785539, exclusion.robots;dur=0.034841, exclusion.robots.policy;dur=0.021809, esindex;dur=0.014275, cdx.remote;dur=8.637252, LoadShardBlock;dur=116.116730, PetaboxLoader3.datanode;dur=50.541280, PetaboxLoader3.resolve;dur=30.934561 x-app-server: wwwb-app202 x-ts: 302 x-tr: 148 server-timing: TR;dur=0,Tw;dur=0,Tc;dur=0 set-cookie: SERVER=wwwb-app202; path=/ x-location: All x-rl: 0 x-na: 0 x-page-cache: MISS server-timing: MISS x-nid: DigitalOcean referrer-policy: no-referrer-when-downgrade permissions-policy: interest-cohort=() HTTP/2 200 server: nginx date: Wed, 16 Jul 2025 05:43:12 GMT content-type: application/x-shar content-length: 7934 x-archive-orig-date: Tue, 10 Feb 2009 08:41:09 GMT x-archive-orig-server: Apache x-archive-orig-last-modified: Mon, 31 Mar 2008 18:10:12 GMT x-archive-orig-etag: "2272c3-1efe-90194900" x-archive-orig-accept-ranges: bytes x-archive-orig-content-length: 7934 x-archive-orig-connection: close cache-control: max-age=1800 x-archive-guessed-content-type: application/x-shar x-archive-guessed-charset: utf-8 memento-datetime: Tue, 10 Feb 2009 08:41:09 GMT link: ; rel="original", ; rel="timemap"; type="application/link-format", ; rel="timegate", ; rel="first memento"; datetime="Sun, 18 Aug 2002 00:42:33 GMT", ; rel="prev memento"; datetime="Wed, 18 Oct 2006 00:10:33 GMT", ; rel="memento"; datetime="Tue, 10 Feb 2009 08:41:09 GMT", ; rel="next memento"; datetime="Wed, 30 Sep 2015 17:27:49 GMT", ; rel="last memento"; datetime="Fri, 25 Mar 2016 03:06:48 GMT" content-security-policy: default-src 'self' 'unsafe-eval' 'unsafe-inline' data: blob: archive.org web.archive.org web-static.archive.org wayback-api.archive.org athena.archive.org analytics.archive.org pragma.archivelab.org wwwb-events.archive.org x-archive-src: 52_8_20090210075601_crawl103-c/52_8_20090210082952_crawl100.arc.gz server-timing: captures_list;dur=0.932515, exclusion.robots;dur=0.041322, exclusion.robots.policy;dur=0.025382, esindex;dur=0.014303, cdx.remote;dur=48.397127, LoadShardBlock;dur=127.920800, PetaboxLoader3.datanode;dur=92.474811, PetaboxLoader3.resolve;dur=97.984752, load_resource;dur=108.941937 x-app-server: wwwb-app202 x-ts: 200 x-tr: 317 server-timing: TR;dur=0,Tw;dur=0,Tc;dur=7 x-location: All x-rl: 0 x-na: 0 x-page-cache: MISS server-timing: MISS x-nid: DigitalOcean referrer-policy: no-referrer-when-downgrade permissions-policy: interest-cohort=() accept-ranges: bytes Newsgroups: comp.sources.misc X-UNIX-From: sherpa!rac organization: Personal System Computing, St. Petersburg, FL keywords: look subject: v15i096: look - find strings in a sorted file from: rac@sherpa.UUCP (Roger Cornelius) Sender: allbery@uunet.UU.NET (Brandon S. Allbery - comp.sources.misc) Posting-number: Volume 15, Issue 96 Submitted-by: rac@sherpa.UUCP (Roger Cornelius) Archive-name: look_rac/part01 Here's a short, fairly fast, fairly portable version of look. The undocumented (at least here) -ttabchar option is not implemented, only because I'm not positive what it does. If someone with access to source can describe its function, I'll add it. I'm also interested to know how this compares in performance to the original. look searches a sorted file for lines beginning with a specified string. See the README for details. No manpage or makefile, just cc -O look.c -o look. -- Roger A. Cornelius rac@sherpa.UUCP uunet!sherpa!rac ---- cut here --- #! /bin/sh # This is a shell archive. Remove anything before this line, then unpack # it by saving it into a file and typing "sh file". To overwrite existing # files, type "sh file -c". You can also feed this as standard input via # unshar, or by typing "sh 'README' <<'END_OF_FILE' X X Here's a short, fairly fast, fairly portable version of look. The X undocumented (at least here) -ttabchar option is not implemented, X only because I'm not positive what it does. If someone with access X to source can describe its function, I'll add it. I'm also interested X to know how this compares speedwise to the original. X X Usage: look [-df] string [file] X file is assumed to be sorted. X The d and f options behave as in sort(1). X If -d is given, only letters, digits, tabs and blanks are compared. X If -f is given, uppercase letters are folded to lowercase - i.e., X the search is case insensitive. X If no file is specified, -df and /usr/dict/words are assumed. X Return status: 0 if search was successful, 1 if not, and 2 on error. X X To build, just cc -O look.c -o look. X tolower() is assumed to do the right thing with non-alpha characters. X Bug reports/comments welcome. X X Roger Cornelius X -- X Roger A. Cornelius rac@sherpa.UUCP uunet!sherpa!rac END_OF_FILE if test 1032 -ne `wc -c <'README'`; then echo shar: \"'README'\" unpacked with wrong size! fi # end of 'README' fi if test -f 'look.c' -a "${1}" != "-c" ; then echo shar: Will not clobber existing file \"'look.c'\" else echo shar: Extracting \"'look.c'\" \(4425 characters\) sed "s/^X//" >'look.c' <<'END_OF_FILE' X/* X * look - search a sorted file for lines beginning with string X * Roger Cornelius (rac@sherpa.uucp) X * Fri Oct 26 13:13:54 EDT 1990 X * public domain X */ X X#define _USE_MACROS /* for SCO UNIX, see ctype.h */ X#include X#include X#include X#include X#include X#define ERR 2 X Xextern void exit(); Xint dstrncmp(); Xoff_t backup(); XFILE *fopen(); Xint fold = 0; Xint dict = 0; Xint (*compare)(); X Xmain(argc, argv) X register int argc; X register char **argv; X{ X extern int optind; X char *file = "/usr/dict/words"; X char *string; X int ch; X X while ((ch = getopt(argc, argv, "df?")) != -1) X switch(ch) { X case 'd': dict = 1; break; X case 'f': fold = 1; break; X case '?': goto usage; X } X argc -= optind; X argv += optind; X X if (argc < 1 || argc > 2) { Xusage: (void)fputs("Usage: look [-df] string [file]\n", stderr); X exit(ERR); X } X string = *argv; X if (*++argv) X file = *argv; X else X fold = dict = 1; X X return search(string, file); X} X X/* X * search -- X * search a sorted file for lines beginning with string X * adapted from binsearch(), K&R 2nd ed. X */ Xstatic Xsearch(string, file) X char *string; X char *file; X{ X FILE *fp; X char buf[BUFSIZ], save[BUFSIZ]; X off_t low, mid, high, savemid = -1; X off_t found = -1; X register char *t; X struct stat sbuf; X size_t slen = strlen(string); X int n, res = 1; /* not found */ X X if ((fp = freopen(file, "r", stdin)) == NULL X || stat(file, &sbuf) != 0) { X /* avoid the printf kitchen sink */ X (void) fputs("look: can't access ", stderr); X (void) fputs(file, stderr); X (void) fputs("\n", stderr); X return ERR; X } X low = 0; X high = sbuf.st_size; X compare = dict ? dstrncmp : strncmp; X if (fold) X for (t=string; *t; *t = tolower(*t), t++) X ; X X while (low < high) { X mid = (low+high) / 2; X if (backup(&low, &mid, &high) == -1 || mid == savemid) X break; X savemid = mid; X if (fseek(fp, mid, 0) != 0 || gets(buf) == NULL) X return ERR; X X if (fold) X for (t=buf; *t; *t = tolower(*t), t++) X ; X n = (*compare)(string, buf, slen); X if (n < 0) X high = mid - 1; X else if (n > 0) X low = mid + 1; X else { X found = mid; /* save offset of found string */ X high = mid - 1; X if (strlen(buf) == slen) X break; X } X } X if (found >= 0) { X if (fseek(fp, found, 0) != 0) X return ERR; X while (gets(buf) != NULL) { X if (fold) { X (void)strcpy(save, buf); X for (t=buf; *t; *t = tolower(*t), t++) X ; X } X if ((*compare)(string, buf, slen) != 0) X break; X (void)puts(fold ? save : buf); X } X res = 0; /* found */ X } X (void)fclose(fp); X return res; X} X X/* X * backup -- X * search backwards for newline - if none found X * then reverse direction and start over X */ Xstatic off_t Xbackup(low, offset, high) X register off_t *low, *offset, *high; X{ X register int c; X register int inc = -1; X off_t save = *offset; X X if (*offset == 0) X return(*offset); X X for (; *offset < *high && fseek(stdin, *offset, 0) == 0; *offset += inc) { X c = getchar(); X if (c == '\n' || *offset == 0) X return (*offset == 0) ? *offset : (*offset)++; X else if (c == EOF) /* should never happen */ X break; X if (*offset <= *low) { /* start over, reversing direction */ X *offset = save; X inc = 1; X } X } X return -1L; X} X X/* X * dstrncmp -- X * dictionary strncmp() - only alpha characters, X * digits, blanks and tabs participate in comparisons X */ Xstatic Xdstrncmp(s1, s2, n) X register char *s1, *s2; X register size_t n; X{ X for (; n--; s1++, s2++) { X while (*s1 && !(isalpha(*s1) || isdigit(*s1) || isspace(*s1))) X s1++; X if (*s1 == '\0') X break; X while (*s2 && !(isalpha(*s2) || isdigit(*s2) || isspace(*s2))) X s2++; X if (*s1 != *s2) X return *s1 - *s2; X } X return 0; X} X X/* end of look.c */ END_OF_FILE if test 4425 -ne `wc -c <'look.c'`; then echo shar: \"'look.c'\" unpacked with wrong size! fi # end of 'look.c' fi echo shar: End of shell archive. exit 0 -- Roger A. Cornelius rac@sherpa.UUCP uunet!sherpa!rac