🚀 go-pugleaf

Submitted-by: NONE
Posting-number: Volume 1, Source:18
Archive-name: util/tail
Architecture: ANY_2
Version-number: 1.00

This C utility prints the first/last N lines/characters of a
file.  Like more or page, but allows you to see only a portion
of the beginning/end of a file. 

Enjoy.

=tail.c
-
-/*
- * tail.c
- *
- * Print first/last N lines/characters part of a file.
- *
- * Usage:
- * 	tail [(-|+)number][lc] [file_1] [file_2] [file_3] [...]
- *	tail [(-|+)number][lc] [file_1] [file_2] [file_3] [...]
- *
- *	Options:
- *        	-	tail last <number> lines from file
- *        	+	begin with line <number>
- *        	l	<number> indicates lines (default)
- *        	c	<number> indicates characters
- *
- *	If no files are specified, tail reads from standard in.
- *
- * Contributed Anonymously.  Written: November 1983
- *
- * Version 1.00
- *
- */
-
-#include "stdio.h"
-
-#define TRUE  1
-#define FALSE 0
-#define BLANK ' '
-#define TAB   '\t'
-#define NL    '\n'
-#define EOS   '\0'
-
-int lines, chars ;
-
-main(argc, argv)
-int argc ;
-char *argv[] ;
-{
-	char *s ;
-	FILE *input ;
-	int count ;
-
-
-	argc-- ; argv++ ;
-	lines = TRUE ;
-	chars = FALSE ;
-	count = -10 ;
-
-	if( argc == 0 ) {
-		tail( stdin, count ) ;
-		exit(0) ;
-	}
-
-	s = *argv ;
-	if( *s == '-' || *s == '+' ) {
-		s++ ;
-		if( *s >= '0' && *s <= '9' ) {
-			count = stoi( *argv ) ;
-			s++ ;
-			while( *s >= '0' && *s <= '9' )
-				s++ ;
-		}
-		if( *s == 'c' ) {
-			chars = TRUE ;
-			lines = FALSE ;
-		}
-		else if( *s != 'l' && *s != EOS ) {
-			fprintf(stderr, "tail: unknown option %c\n", *s ) ;
-			argc = 0 ;
-		}
-		argc-- ; argv++ ;
-	}
-
-	if( argc < 0 ) {
-		fprintf(stderr, "usage: tail [+/-[number][lc]] [files]\n");
-		exit(1) ;
-	}
-
-	if( argc == 0 )
-		tail( stdin, count ) ;
-
-	else if( (input=fopen(*argv,"r")) == NULL ) {
-		fprintf(stderr, "tail: can't open %s\n", *argv) ;
-		exit(1) ;
-	}
-	else {
-		tail( input, count ) ;
-		fclose( input ) ;
-	}
-
-	exit(0) ;
-
-} /* end main */
-
-/* stoi - convert string to integer */
-
-stoi(s)
-char *s ;
-{
-	int n, sign ;
-
-	while( *s == BLANK || *s == NL || *s == TAB )
-		s++ ;
-
-	sign = 1 ;
-	if( *s == '+' )
-		s++ ;
-	else if( *s == '-' ) {
-		sign = -1 ;
-		s++ ;
-	}
-	for( n=0 ; *s >= '0' && *s <= '9' ; s++ )
-		n = 10 * n + *s - '0' ;
-	return( sign * n ) ;
-}
-
-/* tail - print 'count' lines/chars */
-
-#define INCR(p)  if(p >= end) p=cbuf ; else p++
-#define BUFSIZE 4098
-
-char cbuf[ BUFSIZE ] ;
-
-tail( in, goal )
-FILE *in ;
-int goal ;
-{
-	int c, count ;
-	char *start, *finish, *end ;
-
-	count = 0 ;
-
-	if( goal > 0 ) {	/* skip */
-
-		if( lines )		/* lines */
-			while( (c=agetc(in)) != EOF ) {
-				if( c == NL )
-					count++ ; 
-				if( count >= goal )
-					break ;
-			}
-		else			/* chars */
-			while( agetc(in) != EOF ) {
-				count++ ;
-				if( count >= goal )
-					break ;
-			}
-		if( count >= goal )
-			while( (c=agetc(in)) != EOF )
-				aputc(c, stdout ) ;
-	}
-
-	else {				/* tail */
-
-		goal = -goal ;
-		start = finish = cbuf ;
-		end = &cbuf[ BUFSIZE - 1 ] ;
-
-		while( (c=agetc(in)) != EOF ) {
-			*finish = c ;
-			INCR( finish ) ;
-
-			if( start == finish )
-				INCR( start ) ;
-			if( !lines || c == NL )
-				count++ ;
-
-			if( count > goal ) {
-				count = goal ;
-				if( lines )
-					while( *start != NL )
-						INCR( start ) ;
-				INCR( start ) ;
-			}
-
-		} /* end while */
-
-		while( start != finish ) {
-			aputc( *start, stdout ) ;
-			INCR( start ) ;
-		}
-
-	} /* end else */
-
-} /* end tail */
-
-
+ END OF ARCHIVE