1b37b9a6dSNate Williams.Dd June 21, 1993 2b37b9a6dSNate Williams.Dt GETOPT 1 3b37b9a6dSNate Williams.Os 4b37b9a6dSNate Williams.Sh NAME 5b37b9a6dSNate Williams.Nm getopt 6b37b9a6dSNate Williams.Nd parse command options 7b37b9a6dSNate Williams.Sh SYNOPSIS 8b37b9a6dSNate Williams.Nm set \-\- \`getopt optstring $*\` 9b37b9a6dSNate Williams.Sh DESCRIPTION 10b37b9a6dSNate Williams.Nm Getopt 11b37b9a6dSNate Williamsis used to break up options in command lines for easy parsing by 12b37b9a6dSNate Williamsshell procedures, and to check for legal options. 13b37b9a6dSNate Williams.Op Optstring 14b37b9a6dSNate Williamsis a string of recognized option letters (see 15b37b9a6dSNate Williams.Xr getopt 3 16b37b9a6dSNate Williams); 17b37b9a6dSNate Williamsif a letter is followed by a colon, the option 18b37b9a6dSNate Williamsis expected to have an argument which may or may not be 19b37b9a6dSNate Williamsseparated from it by white space. 20b37b9a6dSNate WilliamsThe special option 21b37b9a6dSNate Williams.B \-\- 22b37b9a6dSNate Williamsis used to delimit the end of the options. 23b37b9a6dSNate Williams.Nm Getopt 24b37b9a6dSNate Williamswill place 25b37b9a6dSNate Williams.B \-\- 26b37b9a6dSNate Williamsin the arguments at the end of the options, 27b37b9a6dSNate Williamsor recognize it if used explicitly. 28b37b9a6dSNate WilliamsThe shell arguments 29b37b9a6dSNate Williams(\fB$1 $2\fR ...) are reset so that each option is 30b37b9a6dSNate Williamspreceded by a 31b37b9a6dSNate Williams.B \- 32b37b9a6dSNate Williamsand in its own shell argument; 33b37b9a6dSNate Williamseach option argument is also in its own shell argument. 34b37b9a6dSNate Williams.Sh EXAMPLE 35b37b9a6dSNate WilliamsThe following code fragment shows how one might process the arguments 36b37b9a6dSNate Williamsfor a command that can take the options 37b37b9a6dSNate Williams.Op a 38b37b9a6dSNate Williamsand 39b37b9a6dSNate Williams.Op b , 40b37b9a6dSNate Williamsand the option 41b37b9a6dSNate Williams.Op o , 42b37b9a6dSNate Williamswhich requires an argument. 43b37b9a6dSNate Williams.Pp 44b37b9a6dSNate Williams.Bd -literal -offset indent 45b37b9a6dSNate Williamsset \-\- \`getopt abo: $*\` 46b37b9a6dSNate Williamsif test $? != 0 47b37b9a6dSNate Williamsthen 48b37b9a6dSNate Williams echo 'Usage: ...' 49b37b9a6dSNate Williams exit 2 50b37b9a6dSNate Williamsfi 51b37b9a6dSNate Williamsfor i 52b37b9a6dSNate Williamsdo 53b37b9a6dSNate Williams case "$i" 54b37b9a6dSNate Williams in 55b37b9a6dSNate Williams \-a|\-b) 56b37b9a6dSNate Williams flag=$i; shift;; 57b37b9a6dSNate Williams \-o) 58b37b9a6dSNate Williams oarg=$2; shift; shift;; 59b37b9a6dSNate Williams \-\-) 60b37b9a6dSNate Williams shift; break;; 61b37b9a6dSNate Williams esac 62b37b9a6dSNate Williamsdone 63b37b9a6dSNate Williams.Ed 64b37b9a6dSNate Williams.Pp 65b37b9a6dSNate WilliamsThis code will accept any of the following as equivalent: 66b37b9a6dSNate Williams.Pp 67b37b9a6dSNate Williams.Bd -literal -offset indent 68b37b9a6dSNate Williamscmd \-aoarg file file 69b37b9a6dSNate Williamscmd \-a \-o arg file file 70b37b9a6dSNate Williamscmd \-oarg -a file file 71b37b9a6dSNate Williamscmd \-a \-oarg \-\- file file 72b37b9a6dSNate Williams.Ed 73b37b9a6dSNate Williams.Sh SEE ALSO 74b37b9a6dSNate Williams.Xr sh 1 , 75b37b9a6dSNate Williams.Xr getopt 3 76b37b9a6dSNate Williams.Sh DIAGNOSTICS 77b37b9a6dSNate Williams.Nm Getopt 78b37b9a6dSNate Williamsprints an error message on the standard error output when it 79b37b9a6dSNate Williamsencounters an option letter not included in 80b37b9a6dSNate Williams.Op optstring . 81b37b9a6dSNate Williams.Sh HISTORY 82b37b9a6dSNate WilliamsWritten by Henry Spencer, working from a Bell Labs manual page. 83b37b9a6dSNate WilliamsBehavior believed identical to the Bell version. 84b37b9a6dSNate Williams.Sh BUGS 85b37b9a6dSNate WilliamsWhatever 86b37b9a6dSNate Williams.Xr getopt 3 87b37b9a6dSNate Williamshas. 88b37b9a6dSNate Williams.Pp 89b37b9a6dSNate WilliamsArguments containing white space or imbedded shell metacharacters 90b37b9a6dSNate Williamsgenerally will not survive intact; this looks easy to fix but isn't. 91b37b9a6dSNate Williams.Pp 92b37b9a6dSNate WilliamsThe error message for an invalid option is identified as coming 93b37b9a6dSNate Williamsfrom 94b37b9a6dSNate Williams.Nm getopt 95b37b9a6dSNate Williamsrather than from the shell procedure containing the invocation 96b37b9a6dSNate Williamsof 97b37b9a6dSNate Williams.Nm getopt ; 98b37b9a6dSNate Williamsthis again is hard to fix. 99b37b9a6dSNate Williams.Pp 100b37b9a6dSNate WilliamsThe precise best way to use the 101b37b9a6dSNate Williams.Nm set 102b37b9a6dSNate Williamscommand to set the arguments without disrupting the value(s) of 103b37b9a6dSNate Williamsshell options varies from one shell version to another. 104b37b9a6dSNate Williamsvaries from one shell version to another. 105