read.1 (1806B)
1 .TH CAT 1 2 .SH NAME 3 cat, read, nobs \- catenate files 4 .SH SYNOPSIS 5 .B cat 6 [ 7 .I file ... 8 ] 9 .br 10 .B read 11 [ 12 .B -c 13 ] [ 14 [ 15 .B -m 16 ] [ 17 .B -n 18 .I nline 19 ] [ 20 .I file ... 21 ] 22 .br 23 .B nobs 24 [ 25 .I file ... 26 ] 27 .SH DESCRIPTION 28 .I Cat 29 reads each 30 .I file 31 in sequence and writes it on the standard output. 32 Thus 33 .IP 34 .L 35 cat file 36 .LP 37 prints a file and 38 .IP 39 .L 40 cat file1 file2 >file3 41 .LP 42 concatenates the first two files and places the result 43 on the third. 44 .PP 45 If no 46 .I file 47 is given, 48 .I cat 49 reads from the standard input. 50 Output is buffered in blocks matching the input. 51 .PP 52 .I Read 53 copies to standard output exactly one line from the named 54 .IR file , 55 default standard input. 56 It is useful in interactive 57 .IR rc (1) 58 scripts. 59 .PP 60 The 61 .B -m 62 flag causes it to continue reading and writing multiple lines until end of file; 63 .B -n 64 causes it to read no more than 65 .I nline 66 lines. 67 .PP 68 With the 69 .B -c 70 flag, 71 .I read 72 copies exactly 73 .I nbytes 74 of characters instead of lines. It is mutually exclusive with 75 .B -n 76 and 77 .B -m 78 flag. 79 .PP 80 .I Read 81 always executes a single 82 .B write 83 for each line of input, which can be helpful when 84 preparing input to programs that expect line-at-a-time data. 85 It never reads any more data from the input than it prints to the output. 86 .PP 87 .I Nobs 88 copies the named files to 89 standard output except that it removes all backspace 90 characters and the characters that precede them. 91 It is useful to use as 92 .B $PAGER 93 with the Unix version of 94 .IR man (1) 95 when run inside a 96 .I win 97 (see 98 .IR acme (1)) 99 window. 100 .SH SOURCE 101 .B \*9/src/cmd/cat.c 102 .br 103 .B \*9/src/cmd/read.c 104 .br 105 .B \*9/bin/nobs 106 .SH SEE ALSO 107 .IR cp (1) 108 .SH DIAGNOSTICS 109 .I Read 110 exits with status 111 .B eof 112 on end of file or, in the 113 .B -n 114 case, if it doesn't read 115 .I nlines 116 lines. 117 .SH BUGS 118 Beware of 119 .L "cat a b >a" 120 and 121 .LR "cat a b >b" , 122 which 123 destroy input files before reading them.