1shell_builtins(1) User Commands shell_builtins(1)
2
6 shell_builtins, case, for, foreach, function, if, repeat, select,
7 switch, until, while - shell command interpreter built-in commands
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10 The shell command interpreters csh(1), ksh(1), ksh93(1), and sh(1) have
11 special built-in commands. The commands case, for, foreach, function,
12 if, repeat, select, switch, until, and while are commands in the syntax
13 recognized by the shells. They are described in the Commands section of
14 the manual pages of the respective shells. In ksh93(1), fc, hash, stop,
15 suspend, times, and type are aliases by default. In ksh93, the follow‐
16 ing built-ins are bound to the /bin pathname by default and are invoked
17 if the pathname search encounters an executable command of that name in
18 the /bin or /usr/bin directory: cat, chown, getconf, head, mkdir,
19 rmdir, tee, uniq, and wc.
20 The remaining commands listed in the following table are built into the
23 shells for reasons such as efficiency or data sharing between command
24 invocations. They are described on their respective manual pages.
25 Command Shell
30 ───────────────────────────────────────────────────────────
31 ++**alias csh, ksh, ksh93
32 bg csh, ksh, ksh93, sh
33 +*break csh, ksh, ksh93, sh
34 builtin ksh93
35 case csh, ksh, ksh93, sh
36 cat ksh93
37 cd csh, ksh, ksh93, sh
38 chdir csh, sh
39 chown ksh93
40 command ksh93
41 +*continue csh, ksh, ksh93, sh
42 dirs csh
43 disown ksh93
44 echo csh, ksh, ksh93, sh
45 +*eval csh, ksh, ksh93, sh
46 +*exec csh, ksh, ksh93, sh
47 +*exit csh, ksh, ksh93, sh
48 ++**export ksh, ksh93, sh
49 false ksh, ksh93
50 fc ksh, ksh93
51 fg csh, ksh, ksh93, sh
52 for ksh, ksh93, sh
53 foreach csh
54 function ksh, ksh93
55 getconf ksh93
56 getopts ksh, ksh93, sh
57 glob csh
58 goto csh
59 hash ksh, ksh93, sh
60 hashstat csh
61 head ksh93
62 hist ksh93
63 history csh
64 if csh, ksh, ksh93, sh
65 jobs csh, ksh, ksh93, sh
66 kill csh, ksh, ksh93, sh
68 let ksh, ksh93,
69 limit csh
70 login csh, ksh, ksh93, sh
71 logout csh
72 mkdir ksh93
73 nice csh
74 +*newgrp ksh, ksh93, sh
75 nohup csh
76 notify csh
77 onintr csh
78 popd csh
79 print ksh, ksh93
80 printf ksh93
81 pushd csh
82 pwd ksh, ksh93, sh
83 read ksh, ksh93, sh
84 ++**readonly ksh, ksh93, sh
85 rehash csh
86 repeat csh
87 +*return ksh, ksh93, sh
88 select ksh, ksh93
89 +set csh, ksh, ksh93, sh
90 setenv csh
91 shift csh, ksh, ksh93, sh
92 sleep ksh93
93 source csh
94 stop csh, ksh, ksh93, sh
95 suspend csh, ksh, sh
96 switch csh
97 tee ksh93
98 test ksh, ksh93, sh
99 time csh
100 *times ksh, ksh93, sh
101 *+trap ksh, ksh93, sh
102 true ksh, ksh93
103 type ksh, ksh93, sh
104 ++**typeset ksh, ksh93
105 ulimit ksh, ksh93, sh
106 umask csh, ksh, ksh93, sh
107 +unalias csh, ksh, ksh93
108 unhash csh
109 uniq ksh93
110 unlimit csh
111 +unset csh, ksh, ksh93, sh
112 unsetenv csh
113 until ksh, ksh93, sh
114 *wait csh, ksh, ksh93, sh
115 whence ksh, ksh93
116 while csh, ksh, ksh93, sh
117 Bourne Shell, sh, Special Commands
120 Input/output redirection is now permitted for these commands. File
121 descriptor 1 is the default output location. When Job Control is
122 enabled, additional Special Commands are added to the shell's environ‐
123 ment.
124 In addition to these built-in reserved command words, sh also uses:
127 : No effect; the command does nothing. A zero exit code is
129 returned.
130 .filename Read and execute commands from filename and return. The
133 search path specified by PATH is used to find the direc‐
134 tory containing filename.
135 C shell, csh
138 Built-in commands are executed within the C shell. If a built-in com‐
139 mand occurs as any component of a pipeline except the last, it is exe‐
140 cuted in a subshell. In addition to these built-in reserved command
141 words, csh also uses:
142 : Null command. This command is interpreted, but performs no action.
144 Korn Shell, ksh, Special Commands
147 Input/Output redirection is permitted. Unless otherwise indicated, the
148 output is written on file descriptor 1 and the exit status, when there
149 is no syntax error, is zero.
150 Commands that are preceded by one or two * (asterisks) are treated spe‐
153 cially in the following ways:
154 1. Variable assignment lists preceding the command remain in
156 effect when the command completes.
157 2. I/O redirections are processed after variable assignments.
159 3. Errors cause a script that contains them to abort.
161 4. Words, following a command preceded by ** that are in the
163 format of a variable assignment, are expanded with the same
164 rules as a variable assignment. This means that tilde sub‐
165 stitution is performed after the = sign and word splitting
166 and file name generation are not performed.
167 In addition to these built-in reserved command words, ksh also uses:
170 * : [ arg ... ] The command only expands parameters.
172 * .file [ arg ... ] Read the complete file then execute the
175 commands. The commands are executed in the
176 current shell environment. The search path
177 specified by PATH is used to find the
178 directory containing file. If any argu‐
179 ments arg are specified, they become the
180 positional parameters. Otherwise, the
181 positional parameters are unchanged. The
182 exit status is the exit status of the last
183 command executed. the loop termination
184 test.
185 Korn Shell, ksh93, Special Commands
188 Input/Output redirection is permitted. Unless otherwise indicated, the
189 output is written on file descriptor 1 and the exit status, when there
190 is no syntax error, is zero.
191 Except for :, true, false, echo, newgrp, and login, all built-in com‐
194 mands accept -- to indicate end of options. They also interpret the
195 option --man as a request to display the manual page onto standard
196 error and -? as a help request which prints a usage message on standard
197 error.
198 Commands that are preceded by one or two + are treated specially in the
201 following ways:
202 1. Variable assignment lists preceding the command remain in
204 effect when the command completes.
205 2. I/O redirections are processed after variable assignments.
207 3. Errors cause a script that contains them to abort.
209 4. They are not valid function names.
211 5. Words, following a command preceded by ++ that are in the
213 format of a variable assignment, are expanded with the same
214 rules as a variable assignment. This means that tilde sub‐
215 stitution is performed after the = sign and field splitting
216 and file name generation are not performed.
217 In addition to these built-in reserved command words, ksh93 also uses:
220 : [ arg ... ] The command only expands parameters.
222 .name [ arg ... ] If name is a function defined with the func‐
225 tion name reserved word syntax, the function
226 is executed in the current environment (as
227 if it had been defined with the name() syn‐
228 tax.) Otherwise if name refers to a file,
229 the file is read in its entirety and the
230 commands are executed in the current shell
231 environment. The search path specified by
232 PATH is used to find the directory contain‐
233 ing the file. If any arguments arg are spec‐
234 ified, they become the positional parameters
235 while processing the . command and the orig‐
236 inal positional parameters are restored upon
237 completion. Otherwise the positional parame‐
238 ters are unchanged. The exit status is the
239 exit status of the last command executed.
240
243 Intro(1), alias(1), break(1), builtin(1), cd(1), chmod(1), csh(1), dis‐
244 own(1), echo(1), exec(1), exit(1), find(1), getoptcvt(1), getopts(1),
245 glob(1), hash(1), history(1), jobs(1), kill(1), ksh(1), ksh93(1),
246 let(1), limit(1), login(1), logout(1), newgrp(1), nice(1), nohup(1),
247 print(1), printf(1), pwd(1), read(1), readonly(1), set(1), sh(1),
248 shift(1), sleep(1), suspend(1), test(1)test(1), test(1B), time(1),
249 times(1), trap(1), typeset(1), umask(1), wait(1), chdir(2), chmod(2),
250 creat(2), umask(2), getopt(3C), profile(4), environ(5)
251SunOS 5.11 20 Nov 2007 shell_builtins(1)