DragonFly On-Line Manual Pages

Search: Section:  


BUILTIN(1)             DragonFly General Commands Manual            BUILTIN(1)

NAME

builtin, !, %, ., :, @, [, {, }, alias, alloc, bg, bind, bindkey, break, breaksw, builtins, case, cd, chdir, command, complete, continue, default, dirs, do, done, echo, echotc, elif, else, end, endif, endsw, esac, eval, exec, exit, export, false, fc, fg, filetest, fi, for, foreach, getopts, glob, goto, hash, hashstat, history, hup, if, jobid, jobs, kill, let, limit, local, log, login, logout, ls-F, nice, nohup, notify, onintr, popd, printenv, printf, pushd, pwd, read, readonly, rehash, repeat, return, sched, set, setenv, settc, setty, setvar, shift, source, stop, suspend, switch, telltc, termname, test, then, time, times, trap, true, type, ulimit, umask, unalias, uncomplete, unhash, unlimit, unset, unsetenv, until, wait, where, which, while, wordexp, wordexp2 - shell built-in commands

SYNOPSIS

See the built-in command description in the appropriate shell manual page.

DESCRIPTION

Shell builtin commands are commands that can be executed within the running shell's process. Note that, in the case of csh(1) builtin commands, the command is executed in a subshell if it occurs as any component of a pipeline except the last. If a command specified to the shell contains a slash `/', the shell will not execute a builtin command, even if the last component of the specified command matches the name of a builtin command. Thus, while specifying "echo" causes a builtin command to be executed under shells that support the echo builtin command, specifying "/bin/echo" or "./echo" does not. While some builtin commands may exist in more than one shell, their operation may be different under each shell which supports them. Below is a table which lists shell builtin commands, the standard shells that support them and whether they exist as standalone utilities. Only builtin commands for the csh(1) and sh(1) shells are listed here. Consult a shell's manual page for details on the operation its builtin commands. Beware that the sh(1) manual page, at least, calls some of these commands "built-in commands" and some of them "reserved words". Users of other shells may need to consult an info(1) page or other sources of documentation. Commands marked "No**" under External do exist externally, but are implemented as scripts using a builtin command of the same name. Command External csh(1) sh(1) ! No No Yes % No Yes No . No No Yes : No Yes Yes @ No Yes No [ Yes No Yes { No No Yes } No No Yes alias No** Yes Yes alloc No Yes No bg No** Yes Yes bind No No Yes bindkey No Yes No break No Yes Yes breaksw No Yes No builtin No No Yes builtins No Yes No case No Yes Yes cd No** Yes Yes chdir No Yes Yes command No** No Yes complete No Yes No continue No Yes Yes default No Yes No dirs No Yes No do No No Yes done No No Yes echo Yes Yes Yes echotc No Yes No elif No No Yes else No Yes Yes end No Yes No endif No Yes No endsw No Yes No esac No No Yes eval No Yes Yes exec No Yes Yes exit No Yes Yes export No No Yes false Yes No Yes fc No** No Yes fg No** Yes Yes filetest No Yes No fi No No Yes for No No Yes foreach No Yes No getopts No** No Yes glob No Yes No goto No Yes No hash No No Yes hashstat No Yes No history No Yes No hup No Yes No if No Yes Yes jobid No No Yes jobs No** Yes Yes kill Yes Yes Yes let No No Yes limit No Yes No local No No Yes log No Yes No login Yes Yes No logout No Yes No ls-F No Yes No nice Yes Yes No nohup Yes Yes No notify No Yes No onintr No Yes No popd No Yes No printenv Yes Yes No printf Yes No Yes pushd No Yes No pwd Yes No Yes read No** No Yes readonly No No Yes rehash No Yes No repeat No Yes No return No No Yes sched No Yes No set No Yes Yes setenv No Yes No settc No Yes No setty No Yes No setvar No No Yes shift No Yes Yes source No Yes No stop No Yes No suspend No Yes No switch No Yes No telltc No Yes No termname No Yes No test Yes No Yes then No No Yes time Yes Yes No times No No Yes trap No No Yes true Yes No Yes type No No Yes ulimit No No Yes umask No** Yes Yes unalias No** Yes Yes uncomplete No Yes No unhash No Yes No unlimit No Yes No unset No Yes Yes unsetenv No Yes No until No No Yes wait No** Yes Yes where No Yes No which Yes Yes No while No Yes Yes wordexp No No Yes wordexp2 No No Yes Note that the wordexp and wordexp2 commands are only meant to be used by wordexp(3) and not by the user.

SEE ALSO

csh(1), echo(1), false(1), info(1), kill(1), login(1), nice(1), nohup(1), printenv(1), printf(1), pwd(1), sh(1), test(1), time(1), true(1), which(1), wordexp(3)

HISTORY

The builtin manual page first appeared in FreeBSD 3.4.

AUTHORS

This manual page was written by Sheldon Hearn <sheldonh@FreeBSD.org>. DragonFly 5.9-DEVELOPMENT October 9, 2020 DragonFly 5.9-DEVELOPMENT foreach(n) Tcl Built-In Commands foreach(n) ______________________________________________________________________________

NAME

foreach - Iterate over all elements in one or more lists

SYNOPSIS

foreach varname list body foreach varlist1 list1 ?varlist2 list2 ...? body ______________________________________________________________________________

DESCRIPTION

The foreach command implements a loop where the loop variable(s) take on values from one or more lists. In the simplest case there is one loop variable, varname, and one list, list, that is a list of values to assign to varname. The body argument is a Tcl script. For each element of list (in order from first to last), foreach assigns the contents of the element to varname as if the lindex command had been used to extract the element, then calls the Tcl interpreter to execute body. In the general case there can be more than one value list (e.g., list1 and list2), and each value list can be associated with a list of loop variables (e.g., varlist1 and varlist2). During each iteration of the loop the variables of each varlist are assigned consecutive values from the corresponding list. Values in each list are used in order from first to last, and each value is used exactly once. The total number of loop iterations is large enough to use up all the values from all the value lists. If a value list does not contain enough elements for each of its loop variables in each iteration, empty values are used for the missing elements. The break and continue statements may be invoked inside body, with the same effect as in the for command. Foreach returns an empty string.

EXAMPLES

This loop prints every value in a list together with the square and cube of the value: set values {1 3 5 7 2 4 6 8} ;# Odd numbers first, for fun! puts "Value\tSquare\tCube" ;# Neat-looking header foreach x $values { ;# Now loop and print... puts " $x\t [expr {$x**2}]\t [expr {$x**3}]" } The following loop uses i and j as loop variables to iterate over pairs of elements of a single list. set x {} foreach {i j} {a b c d e f} { lappend x $j $i } # The value of x is "b a d c f e" # There are 3 iterations of the loop. The next loop uses i and j to iterate over two lists in parallel. set x {} foreach i {a b c} j {d e f g} { lappend x $i $j } # The value of x is "a d b e c f {} g" # There are 4 iterations of the loop. The two forms are combined in the following example. set x {} foreach i {a b c} {j k} {d e f g} { lappend x $i $j $k } # The value of x is "a d e b f g c {} {}" # There are 3 iterations of the loop.

SEE ALSO

for(n), while(n), break(n), continue(n)

KEYWORDS

foreach, iteration, list, loop Tcl foreach(n)

Search: Section: