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If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner] 10 .TH TAIL 1 "Jul 13, 2005" 11 .SH NAME 12 tail \- deliver the last part of a file 13 .SH SYNOPSIS 14 .LP 15 .nf 16 \fB/usr/bin/tail\fR [\(+-s \fInumber\fR [lbcr]] [\fIfile\fR] 17 .fi 18 19 .LP 20 .nf 21 \fB/usr/bin/tail\fR [\fB-lbcr\fR] [\fIfile\fR] 22 .fi 23 24 .LP 25 .nf 26 \fB/usr/bin/tail\fR [\(+- \fInumber\fR [lbcf]] [\fIfile\fR] 27 .fi 28 29 .LP 30 .nf 31 \fB/usr/bin/tail\fR [\fB-lbcf\fR] [\fIfile\fR] 32 .fi 33 34 .LP 35 .nf 36 \fB/usr/xpg4/bin/tail\fR [\fB-f\fR | \fB-r\fR] [\fB-c\fR \fInumber\fR | \fB-n\fR \fInumber\fR] [\fIfile\fR] 37 .fi 38 39 .LP 40 .nf 41 \fB/usr/xpg4/bin/tail\fR [\(+- \fInumber\fR [l | b | c] [f]] [\fIfile\fR] 42 .fi 43 44 .LP 45 .nf 46 \fB/usr/xpg4/bin/tail\fR [\(+- \fInumber\fR [l] [f | r]] [\fIfile\fR] 47 .fi 48 49 .SH DESCRIPTION 50 .sp 51 .LP 52 The \fBtail\fR utility copies the named file to the standard output beginning 53 at a designated place. If no file is named, the standard input is used. 54 .sp 55 .LP 56 Copying begins at a point in the file indicated by the \fB-c\fR\fInumber\fR, 57 \fB-n\fR\fInumber\fR, or \fB\(+-\fR\fInumber\fR options (if \fB+\fR\fInumber\fR 58 is specified, begins at distance number from the beginning; if 59 \fB-\fR\fInumber\fR is specified, from the end of the input; if \fInumber\fR is 60 \fINULL\fR, the value \fB10\fR is assumed). \fInumber\fR is counted in units of 61 lines or byte according to the \fB-c\fR \fB or \fR \fB-n\fR options, or lines, 62 blocks, or bytes, according to the appended option \fBl\fR, \fBb\fR, or 63 \fBc\fR. When no units are specified, counting is by lines. 64 .SH OPTIONS 65 .sp 66 .LP 67 The following options are supported for both \fB/usr/bin/tail\fR and 68 \fB/usr/xpg4/bin/tail\fR. The \fB-r\fR and \fB-f\fR options are mutually 69 exclusive. If both are specified on the command line, the \fB-f\fR option is 70 ignored. 71 .sp 72 .ne 2 73 .na 74 \fB\fB-b\fR \fR 75 .ad 76 .RS 7n 77 Units of blocks. 78 .RE 79 80 .sp 81 .ne 2 82 .na 83 \fB\fB-c\fR \fR 84 .ad 85 .RS 7n 86 Units of bytes. 87 .RE 88 89 .sp 90 .ne 2 91 .na 92 \fB\fB-f\fR \fR 93 .ad 94 .RS 7n 95 Follow. If the input-file is not a pipe, the program does not terminate after 96 the line of the input-file has been copied, but enters an endless loop, wherein 97 it sleeps for a second and then attempts to read and copy further records from 98 the input-file. Thus it can be used to monitor the growth of a file that is 99 being written by some other process. 100 .RE 101 102 .sp 103 .ne 2 104 .na 105 \fB\fB-l\fR \fR 106 .ad 107 .RS 7n 108 Units of lines. 109 .RE 110 111 .sp 112 .ne 2 113 .na 114 \fB\fB-r\fR \fR 115 .ad 116 .RS 7n 117 Reverse. Copies lines from the specified starting point in the file in reverse 118 order. The default for \fBr\fR is to print the entire file in reverse order. 119 .RE 120 121 .SS "/usr/xpg4/bin/tail" 122 .sp 123 .LP 124 The following options are supported for \fB/usr/xpg4/bin/tail\fR only: 125 .sp 126 .ne 2 127 .na 128 \fB\fB-c\fR \fInumber\fR \fR 129 .ad 130 .RS 14n 131 The \fInumber\fR option-argument must be a decimal integer whose sign affects 132 the location in the file, measured in bytes, to begin the copying: 133 .sp 134 .ne 2 135 .na 136 \fB\fB+\fR \fR 137 .ad 138 .RS 9n 139 Copying starts relative to the beginning of the file. 140 .RE 141 142 .sp 143 .ne 2 144 .na 145 \fB\fB\(mi\fR \fR 146 .ad 147 .RS 9n 148 Copying starts relative to the end of the file. 149 .RE 150 151 .sp 152 .ne 2 153 .na 154 \fBnone\fR 155 .ad 156 .RS 9n 157 Copying starts relative to the end of the file. 158 .RE 159 160 The origin for counting is 1; that is, \fB\fR\fB-c\fR\fB+1\fR represents the 161 first byte of the file, \fB\fR\fB-c\fR\fB\(mi1\fR the last. 162 .RE 163 164 .sp 165 .ne 2 166 .na 167 \fB\fB-n\fR \fInumber\fR \fR 168 .ad 169 .RS 14n 170 Equivalent to \fB-c\fR\fInumber,\fR except the starting location in the file is 171 measured in lines instead of bytes. The origin for counting is \fB1\fR. That 172 is, \fB-n\fR\fB+1\fR represents the first line of the file, \fB-n\fR\fB\(mi1\fR 173 the last. 174 .RE 175 176 .SH OPERANDS 177 .sp 178 .LP 179 The following operand is supported: 180 .sp 181 .ne 2 182 .na 183 \fB\fIfile\fR \fR 184 .ad 185 .RS 9n 186 A path name of an input file. If no \fIfile\fR operands are specified, the 187 standard input is used. 188 .RE 189 190 .SH USAGE 191 .sp 192 .LP 193 See \fBlargefile\fR(5) for the description of the behavior of \fBtail\fR when 194 encountering files greater than or equal to 2 Gbyte ( 2^31 bytes). 195 .SH EXAMPLES 196 .LP 197 \fBExample 1 \fRUsing the tail Command 198 .sp 199 .LP 200 The following command prints the last ten lines of the file \fBfred\fR, 201 followed by any lines that are appended to \fBfred\fR between the time 202 \fBtail\fR is initiated and killed. 203 204 .sp 205 .in +2 206 .nf 207 example% \fBtail -f fred\fR 208 .fi 209 .in -2 210 .sp 211 212 .sp 213 .LP 214 The next command prints the last 15 bytes of the file \fBfred\fR, followed by 215 any lines that are appended to \fBfred\fR between the time \fBtail\fR is 216 initiated and killed: 217 218 .sp 219 .in +2 220 .nf 221 example% \fBtail -15cf fred\fR 222 .fi 223 .in -2 224 .sp 225 226 .SH ENVIRONMENT VARIABLES 227 .sp 228 .LP 229 See \fBenviron\fR(5) for descriptions of the following environment variables 230 that affect the execution of \fBtail\fR: \fBLANG\fR, \fBLC_ALL\fR, 231 \fBLC_CTYPE\fR, \fBLC_MESSAGES\fR, and \fBNLSPATH\fR. 232 .SH EXIT STATUS 233 .sp 234 .LP 235 The following exit values are returned: 236 .sp 237 .ne 2 238 .na 239 \fB\fB0\fR \fR 240 .ad 241 .RS 7n 242 Successful completion. 243 .RE 244 245 .sp 246 .ne 2 247 .na 248 \fB\fB>0\fR \fR 249 .ad 250 .RS 7n 251 An error occurred. 252 .RE 253 254 .SH ATTRIBUTES 255 .sp 256 .LP 257 See \fBattributes\fR(5) for descriptions of the following attributes: 258 .SS "/usr/bin/tail" 259 .sp 260 261 .sp 262 .TS 263 box; 264 c | c 265 l | l . 266 ATTRIBUTE TYPE ATTRIBUTE VALUE 267 _ 268 CSI Enabled 269 .TE 270 271 .SS "/usr/xpg4/bin/tail" 272 .sp 273 274 .sp 275 .TS 276 box; 277 c | c 278 l | l . 279 ATTRIBUTE TYPE ATTRIBUTE VALUE 280 _ 281 CSI Enabled 282 _ 283 Interface Stability Standard 284 .TE 285 286 .SH SEE ALSO 287 .sp 288 .LP 289 \fBcat\fR(1), \fBhead\fR(1), \fBmore\fR(1), \fBpg\fR(1), \fBdd\fR(1M), 290 \fBattributes\fR(5), \fBenviron\fR(5), \fBlargefile\fR(5), \fBstandards\fR(5) 291 .SH NOTES 292 .sp 293 .LP 294 Piped tails relative to the end of the file are stored in a buffer, and thus 295 are limited in length. Various kinds of anomalous behavior can happen with 296 character special files.