1cmdline(n) Command line and option processing cmdline(n)
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6
8 cmdline - Procedures to process command lines and options.
9
11 package require Tcl 8.2
12 package require cmdline ?1.3.3?
14 ::cmdline::getopt argvVar optstring optVar valVar
16 ::cmdline::getKnownOpt argvVar optstring optVar valVar
18 ::cmdline::getoptions arglistVar optlist ?usage?
20 ::cmdline::getKnownOptions arglistVar optlist ?usage?
22 ::cmdline::usage optlist ?usage?
24 ::cmdline::getfiles patterns quiet
26 ::cmdline::getArgv0
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30
32 This package provides commands to parse command lines and options.
33
35 One of the most common variables this package will be used with is
36 ::argv, which holds the command line of the current application. This
37 variable has a companion ::argc which is initialized to the number of
38 elements in ::argv at the beginning of the application.
39 The commands in this package will not modify the ::argc companion when
41 called with ::argv. Keeping the value consistent, if such is desired or
42 required, is the responsibility of the caller.
43
45 ::cmdline::getopt argvVar optstring optVar valVar
46 This command works in a fashion like the standard C based getopt
47 function. Given an option string and a pointer to an array of
48 args this command will process the first argument and return
49 info on how to proceed. The command returns 1 if an option was
50 found, 0 if no more options were found, and -1 if an error
51 occurred.
52 argvVar contains the name of the list of arguments to process.
54 If options are found the list is modified and the processed
55 arguments are removed from the start of the list.
56 optstring contains a list of command options that the applica‐
58 tion will accept. If the option ends in ".arg" the command will
59 use the next argument as an argument to the option, or extract
60 it from the current argument, if it is of the form
61 "option=value". Otherwise the option is a boolean that is set
62 to 1 if present.
63 optVar refers to the variable the command will store the found
65 option into (without the leading '-' and without the .arg exten‐
66 sion).
67 valVar refers to the variable to store either the value for the
69 specified option into upon success or an error message in the
70 case of failure. The stored value comes from the command line
71 for .arg options, otherwise the value is 1.
72 ::cmdline::getKnownOpt argvVar optstring optVar valVar
74 Like ::cmdline::getopt, but ignores any unknown options in the
75 input.
76 ::cmdline::getoptions arglistVar optlist ?usage?
78 Processes the set of command line options found in the list
79 variable named by arglistVar and fills in defaults for those not
80 specified. This also generates an error message that lists the
81 allowed flags if an incorrect flag is specified. The optional
82 usage-argument contains a string to include in front of the gen‐
83 erated message. If not present it defaults to "options:".
84 optlist contains a list of lists where each element specifies an
86 option in the form: flag default comment.
87 If flag ends in ".arg" then the value is taken from the command
89 line. Otherwise it is a boolean and appears in the result if
90 present on the command line. If flag ends in ".secret", it will
91 not be displayed in the usage.
92 The options -?, -help, and -- are implicitly understood. The
94 first two abort option processing by throwing an error and force
95 the generation of the usage message, whereas the the last aborts
96 option processing without an error, leaving all arguments coming
97 after for regular processing, even if starting with a dash.
98 The result of the command is a dictionary mapping all options to
100 their values, be they user-specified or defaults.
101 ::cmdline::getKnownOptions arglistVar optlist ?usage?
103 Like ::cmdline::getoptions, but ignores any unknown options in
104 the input.
105 ::cmdline::usage optlist ?usage?
107 Generates and returns an error message that lists the allowed
108 flags. optlist is defined as for ::cmdline::getoptions. The
109 optional usage-argument contains a string to include in front of
110 the generated message. If not present it defaults to "options:".
111 ::cmdline::getfiles patterns quiet
113 Given a list of file patterns this command computes the set of
114 valid files. On windows, file globbing is performed on each
115 argument. On Unix, only file existence is tested. If a file
116 argument produces no valid files, a warning is optionally gener‐
117 ated (set quiet to true).
118 This code also uses the full path for each file. If not given
120 it prepends the current working directory to the filename. This
121 ensures that these files will never conflict with files in a
122 wrapped zip file. The last sentence refers to the pro-tools.
123 ::cmdline::getArgv0
125 This command returns the "sanitized" version of argv0. It will
126 strip off the leading path and removes the extension ".bin". The
127 latter is used by the pro-apps because they must be wrapped by a
128 shell script.
129 ERROR CODES
131 Starting with version 1.5 all errors thrown by the package have a
132 proper ::errorCode for use with Tcl's try command. This code always has
133 the word CMDLINE as its first element.
134
136 package require Tcl 8.5
137 package require try ;# Tcllib.
138 package require cmdline 1.5 ;# First version with proper error-codes.
139 # Notes:
141 # - Tcl 8.6+ has 'try' as a builtin command and therefore does not
142 # need the 'try' package.
143 # - Before Tcl 8.5 we cannot support 'try' and have to use 'catch'.
144 # This then requires a dedicated test (if) on the contents of
145 # ::errorCode to separate the CMDLINE USAGE signal from actual errors.
146 set options {
148 {a "set the atime only"}
149 {m "set the mtime only"}
150 {c "do not create non-existent files"}
151 {r.arg "" "use time from ref_file"}
152 {t.arg -1 "use specified time"}
153 }
154 set usage ": MyCommandName \[options] filename ...\noptions:"
155 try {
157 array set params [::cmdline::getoptions argv $options $usage]
158 } trap {CMDLINE USAGE} {msg o} {
159 # Trap the usage signal, print the message, and exit the application.
160 # Note: Other errors are not caught and passed through to higher levels!
161 puts $msg
162 exit 1
163 }
164 if { $params(a) } { set set_atime "true" }
166 set has_t [expr {$params(t) != -1}]
167 set has_r [expr {[string length $params(r)] > 0}]
168 if {$has_t && $has_r} {
169 return -code error "Cannot specify both -r and -t"
170 } elseif {$has_t} {
171 ...
172 }
173 This example, taken (and slightly modified) from the package fileutil,
176 shows how to use cmdline. First, a list of options is created, then
177 the 'args' list is passed to cmdline for processing. Subsequently,
178 different options are checked to see if they have been passed to the
179 script, and what their value is.
180
182 This document, and the package it describes, will undoubtedly contain
183 bugs and other problems. Please report such in the category cmdline of
184 the Tcllib Trackers [http://core.tcl.tk/tcllib/reportlist]. Please
185 also report any ideas for enhancements you may have for either package
186 and/or documentation.
187 When proposing code changes, please provide unified diffs, i.e the out‐
189 put of diff -u.
190 Note further that attachments are strongly preferred over inlined
192 patches. Attachments can be made by going to the Edit form of the
193 ticket immediately after its creation, and then using the left-most
194 button in the secondary navigation bar.
195
197 argument processing, argv, argv0, cmdline processing, command line pro‐
198 cessing
199
201 Programming tools
202tcllib 1.5 cmdline(n)