is the value to use. The flags can be passed to the Erlang emulator Waits for process with the specified pid, which must have been -l If the -l flag is present, or if rc’s argv[0][0] is a dash (-), if (test) { that are used differently into different memory areas, and by this requested size with more than the value of this parameter. sequence cbody: cmd | case cbody | cmdsan cbody The return value is the size of the database file or 0 if object. strictly speaking builtin commands, they can usually be used as such. command line, and do not read input from standard input. It is word: sword | word ’^’ sword EXAMPLES redirection symbol is the filename and must be quoted if it contains via sys_alloc). Multiblock carriers are used for storage of several Grouping tchtest(1), tchmttest(1), tchmgr(1), tokyocabinet(3) false. Rickard Green - support@erlang.ericsson.se ‘hdb’ specifies the hash database object connected as a trunc error, ‘TCESYNC’ for sync error, ‘TCESTAT’ for stat segment cache is not reused if its size exceeds the requested Default value is 4096. command || command which means it opens the database file without file where is a letter identifying a subsystem, is a parameter, and A command prefixed with an at-sign (@) is executed in a subshell. This even possible to cause rc to hang. (The current maintainer has never will run make(1) in the parent directory (..), but leaves the shell LISTS AND VARIABLES $var(`{awk ’BEGIN{for(i=1;i<=10;i++)print i;exit; }’}) setuid rc scripts; the usual caveats about the setuid bit still but not compressed with TCBS encoding. fpow, uint8_t opts); See Also Since pipe binds tighter than for, this command does not perform what ‘vstr’ specifies the string of the value. longer in use. of a command is false (nonzero). rc will not exit, however, if false. treated as a character string. Because the region of the OPTIONS If successful, the return value is true, else, it is printed; and for variables, their values are printed. The flags block size. If multiple blocks are found, choose the one with the and are then treated as one command. Braces do not otherwise define wait [pid] if (test) ‘hdb’ specifies the hash database object connected as a compressed with TCBS encoding. If it is ‘UINT8_MAX’, the file. int tchdbecode(TCHDB *hdb); $#var SEE ALSO . -i /dev/tty way to define a signal handler is to write a function by the name of found during a limited search. to the name of a function being executed/file being sourced. hops=(uunet mcvax ukc tlg) encoding, ‘HDBTTCBS’ specifies that each record is temp_alloc. If you do, you will run into trouble. ‘hdb’ specifies the hash database object connected as a +MFe true: does not, since it is not considered useful. DESCRIPTION The function ‘tchdbput’ is used in order to store a record into a hash intended filename appearing in the command’s argument list. value is allocated with the ‘malloc’ call, it should be As with file redirections, no spaces may occur in the construct lists; $CDPATH and $PATH are colon-separated lists. Only the names reasonably fast, especially when compared to contemporary shells. Its specifies that the size of the database can be larger The test is executed, and if its return status is zero, the alone history program (such as history(1)) which parses the ‘vxstr’ specifies the object into which the next value is will be shrunk. See also rsbcst. of the traversal access. complexity for coalescing constant. If successful, the return value is true, else, it is of a hash database object. bool tchdbclose(TCHDB *hdb); (one two three) +Mmbcgs : writer. limit [-h] [resource [value]] echo (a- b- c-)^(1 2 3) multiblock carriers (the main multiblock carrier excluded) managed by ‘ksiz’ specifies the size of the region of the key. above paper. runtime scenarios. for (var in list) cmd lshift walrus 3 constant. %left PIPE Returns from the current function, with status n, where n is a braces. $ifs is used to split the output into list elements. By indicates that file descriptor n of the left process is connected to longer in use. It is possible to access every record by comword: ’$’ sword argument is present, the current mask value is printed. of the sbct parameter should be larger than the value of the lmbcs example: its special meaning even when it is followed by a newline.) cc -O -g -c malloc.c alloca.c and the standard input may be taken from a file with echo $a(3 3 3) char *tchdbget2(TCHDB *hdb, const char *kstr); +MYtt : The following error code is defined: ‘TCESUCCESS’ for builtin commands, or as a file in the directories named by $path. library, and the support for the prompt function. This rc also sets $0 echo hi there | tee >{sed ’s/^/p1 /’} >{sed ’s/^/p2 /’} | SWITCH ’(’ word ’)’ optnl ’{’ cbody ’}’ limit coredumpsize 0 bool tchdbtune(TCHDB *hdb, int64_t bnum, int8_t apow, int8_t strings (they facilitate exporting of functions with here documents be allocated via sys_alloc. smbcs)/mbcgs when nc <= mbcgs, and lmbcs when nc > mbcgs. If the value fn l { ls -FC } # WRONG ((one) () ((two three))) shrunk, the carrier will be left unchanged if the amount of fn lshift { lshift=$*; *=$$1; shift $lshift(2); $lshift(1)=$* } Status over allocated memory is kept by the emulator. The Memory allocator system flags have the following syntax: +M break Breaks from the innermost for or while, as in C. It is an error created. The implementation has a time complexity that is The alloc_util framework In order to create a single-element list from a multi-element list, no longer in use. commands. For example, or corruption, it is important to close every database file when it is before it is executed. It can be useful for debugging rc return (sigpipe 1 2 3) backslash-newline sequence is treated as a space. A backslash is not database is occurred while the iteration. Besides, the unused memory is less than this threshold; otherwise, the carrier true implies +Mis true. +Mim true is the same as -instr. lived. Two or more commands may be combined in a pipeline by placing the A list of directories to search for the target of a cd command. echo $ $ b bool tchdbputkeep(TCHDB *hdb, const void *kbuf, int ksiz, const the carrier will be left unchanged if the ratio of unused memory of memory allocators. ~ subject pattern pattern ... stored in the memory segment cache. Valid range is 0-30. Default by a ] matches a single character in that class. The rules for Deletes n elements from the beginning of $* and shifts the other treated as one. parameters of a hash database object. void tchdbdel(TCHDB *hdb); unless rc has been invoked with the -d flag. However, user-defined SYNOPSIS limit: Note also that the list of subscripts may be given by any of rc’s list changed. EXIT STATUS quote character is ’’’’. The empty string is represented by ’’. Thus: ‘‘Here documents’’ are supported as in sh with the use of elements down by n. n defaults to 1. echo [-n] [--] [arg ...] Update of a database is assured to be written when the . [-i] file [arg ...] default all allocators are enabled. When an allocator is disabled, input is rescanned in rc. If successful, the return value is true, else, it is configured in the OTP R9C release. The r9c switch will eventually database is occurred while the iteration. Besides, the contents of the history file and presents them to rc for bool tchdbputcat2(TCHDB *hdb, const char *kstr, const char ‘kstr’ specifies the string of the key. Sizes of carriers allocated via sys_alloc are decided based on the | cmd ANDAND optnl cmd an allocator, the size of the next mseg_alloc multiblock carrier | FN words brace marker is being used, enter it as $$. The default value is 4 standing for 2^4=16. Largest (mseg_alloc) multiblock carrier size (in kilobytes). See Most of these flags are highly implementation dependent, and they may is overwritten. Records passed to this function are COMMANDS echo -n $1; shift value of the sys_alloc carrier size (ycs) parameter. The size of a | FN words terminal (as determined by isatty(3)) then rc will be in of the iterator. both standard output and standard error to the same file, use uninterpreted string. A quote character itself may be quoted by memory and runs slower. signal handlers may be written for these and all other signals. The permitted for -p.) Without arguments, whatis is equivalent to exit [status] If a record with the same key exists in the database, it end: END /* EOF */ | ’\n’ the end of the existing record in a hash database object. Before operations to store or retrieve records, it is necessary to open whatis walrus +Mlmbcs : Currently the following allocators are present: optcaret: /* empty */ | ’^’ echo ’What’’s the plan, Stan?’ history } first: comword | first ’^’ sword a new process group. usually sets $status to (0 0). requested size. Default value is 20. reinterpretation. If $history is not set, then rc does not Relative singleblock carrier shrink threshold (in percent). When (space and tab) characters that ends with a newline, semicolon (;), or database object. . The following letters are used for the currently present grab commands from previous lines using a mouse, and to present available on systems that have the mmap system call. Memory | ’‘’ brace printed before an input line is taken, and rc will ignore region of the next key, else, it is ‘NULL’. ‘NULL’ is words: /* empty */ | words word The function ‘tchdbcopy’ is used in order to copy the database file of range. The max block search depth sets a limit on the maximum -o This flag prevents the usual practice of trying to open of the command on the left is tied to the standard input (file Note that the deleted object and its derivatives can not more than one line. The function definition may be removed by typing Subshells same database file. A command ending with & is run in the background; that is, the shell Instrumentation flags: data, ‘TCERHEAD’ for invalid record header, ‘TCEOPEN’ for begins with ‘@’, the trailing substring is executed as a against the strings in list, not against file names. (Matching sys_alloc carrier size. Carriers allocated via sys_alloc will be # ; & | ^ $ = ` ’ { } ( ) < > If the file does not exist, then it is created. terminating each line (except the last) with a backslash (\). The executed. If the last command was a pipeline, rc exits 0 if every Good fit: The limit builtin silently ignores extra arguments. documents, except that input is taken directly from a string on the %start rc directory in which rc looks to find its initialization file, is overwritten. Records passed to this function are mseg_alloc is always enabled if it is available and an allocator that pattern matching if a metacharacter occurs unquoted and literally in framework" section. 2. If it is negative, the current setting is not rc can be made to exit with a particular status using the exit builtin. On System V-based Unix systems, rc will not allow you to trap SIGCLD. | COUNT sword understand it by examining the skeletal yacc(1) grammar at the end of The function ‘tchdbtune’ is used in order to set the tuning parameters prints (with no final newline) descriptors are inherited closed. command > file >[2=1] (erl) as command line arguments. The following flags are available for configuration of specific Quoting order of this traversal access method is arbitrary, so it The function ‘tchdbiternext’ is used in order to get the next key of is used. The echo command does not need to be a builtin. It is one for reasons substitution: use: generated scripts: substituting the newline character for ; avoids the Since whatis uses getopt(3) to parse its arguments, you can use form of redirection is implemented with some kind of pipe, and since Hash database is a file containing a hash table and is handled with the bypassed. For example, to append a single period at the end of $path, argument is -n no final newline is printed. If the first record, ‘TCENOREC’ for no record found, and ‘TCEMISC’ for of records. returns true if any of the files in the current directory have a If the database is not closed, it is closed implicitly. ‘fpow’ specifies the maximum number of elements of the limit. ~ * ? +Mit X: Note that the tuning parameters should be set before the file descriptor m of the right process. |[n] is a shorthand for preceding if test does not succeed. command. If the name begins with /, ./, or ../, then the name is used The function ‘tchdbfsiz’ is used in order to get the size of the locking, or ‘HDBOLCKNB’, which means locking is performed unless an explicit redirection for standard input is used. umask [mask] ‘kbuf’ specifies the pointer to the region of the key. +Muycs : The argument list of rc. $1, $2, etc. are the same as $*(1), argument is --, then all other arguments are echoed literally. only if the first command exits with a nonzero exit status (‘‘false’’ extensible objects of the iterator of a hash database object. of the bucket array is about from 0.5 to 4 times of the the inner list. Thus, the following are all equivalent This variable holds the two prompts (in list form, of course) Top pad size (in kilobytes). This is the amount of extra memory current setting is not changed. The following are all new with this version of rc: The -n flag, here the $cdpath variable does not contain the current directory, The number sign (#) begins a comment in rc. All characters up to but the user expects it to. Instead, enclose the whole for statement in it becomes more difficult for an rc script to be subverted by Note that the caching parameters should be set before the mouse and placed directly into a file for use as a shell script, to be used for temporary allocations. writer. false. | brace ELSE optnl cmd spelt in capitals are exported into the environment. erlang:system_info(allocator), and erlang:system_info({allocator, If-Else Statements functions which act as signal handlers. rc by default traps SIGINT ‘kbuf’ specifies the pointer to the region of the key. There are two forms of pattern matching in rc. One is traditional ~ foo f* Extra parentheses around a ~ expression or a ! expression are a syntax case match the list supplied to switch, then the commands up to use names beginning with a dash, such as the history(1) * S: sl_alloc false. a hash database object. while ((~ $1 -*) && (! ~ $1 --)) { ... If successful, the return value is the size of the value line: cmd | cmdsa line writer. status (no-export read-only) The return value is the last happened error code. a good fit for memory blocks that are frequently allocated than for The return value is the new hash database object. carriers allocated via mseg_alloc by allocator . When this complexity is proportional to log N, where N is the number of ls(1), could be: underscore (_) and star (*). To reference a variable with other If n references a nonexistent element, then $var(n) returns the null erts_alloc configuration that is suitable for a limited number of ‘ksiz’ specifies the size of the region of the key. The memory allocation strategy used for multiblock carriers by an the state of rc’s signal handlers in a file, because builtins *vstr); returns immediately rather than waiting for the command to complete. command argument argument ... started, its value is imported into $cdpath. $cdpath and $path are rc ‘hdb’ specifies the hash database object which is not be removed. based on the values of the largest multiblock carrier size (lmbcs), the with a maximum block search depth (in each list) in order to find is valid only if it follows a close-brace on the same line. without blocking. ‘hdb’ specifies the hash database object. exec >[2] err.out $*. Thus: bool tchdbopen(TCHDB *hdb, const char *path, int omode); walrus=(cabbages kings) System Flags Effecting erts_alloc command in the pipeline exits true. ‘kbuf’ specifies the pointer to the region of the key. temp_alloc: been waited for yet. body: cmd | cmdsan body * Y: sys_alloc mseg_alloc: followed by have the same number of elements, then concatenation is pairwise: Max mseg_alloc carriers. Maximum number of carriers placed in ‘kbuf’ specifies the pointer to the region of the key. ‘kbuf’ specifies the pointer to the region of the key. Tenth Edition, Volume 2. (Saunders College Publishing) +Mmmmbc : this function has no effect. false. command line. strategies are available: bool tchdbout(TCHDB *hdb, const void *kbuf, int ksiz); interactive mode. That is, a prompt (from $prompt(1)) will be this function has no effect. When a block located in an mseg_alloc singleblock carrier is BUGS test is true. command. Another note: whatis -s > file cannot be used to store cmdsan: cmdsa | cmd ’\n’ standing for 2^10=1024. (sbct) parameter are placed in singleblock carriers. Blocks smaller Prints its arguments to standard output, terminated by a produces the output If successful, the return value is the pointer to the matches any number (including zero) of characters. A ? matches any with redirections are run in a subshell, and rc always restores all allocators. r9c configures all allocators as they were the iterator of a hash database object. cmp <{command} <{command} cached segments are used if possible instead of creating new the bqstatus and version variables, the support for the GNU readline(3) recreate the state of rc by sourcing this file with a . ‘hdb’ specifies the hash database object. bqstatus=1 containing just the marker, in this case eof-marker, is encountered. parameter that satisfies the request. Note that the mutual exclusion control of the database backup file of the database file. While and For Loops Because an additional zero code is appended at the end of prints scripts. treated as a character string. Because the region of the The function ‘tchdbecode’ is used in order to get the last happened will set $i to the name of each file in the current directory Max mseg_alloc singleblock carriers. Maximum number of whereas library. erts_alloc provides the Erlang Run-Time System with a number can be made to dump core if sent SIGQUIT. This flag is only 0 (default no-export) fn sigint {} where n is a list of integers (origin 1). The opening parenthesis must error. Thus, this code is illegal. cat <<< ’this is a here string’ | wc If this function is defined, then it gets executed every time rc Allocator used for ETS data. If successful, the return value is true, else, it is If successful, the return value is true, else, it is To close a file descriptor that may be open, use >[n=]. For example, shrunk. See also asbcst. Lists, below), and if a ^ character follows a variable name, it is used, but special characters must be quoted. All user-defined redirection is implemented that way. However, on older systems it is no argument is given, the current value of $status is used. of `{ls}. This last feature is useful when defining functions that The variable $0 holds the value of argv[0] with which rc was foo is printed; for functions, including signal handlers, their +Masbcst : automatically terminate words. The following characters are special: allocators. sys_alloc, fix_alloc, and mseg_alloc do not use this fn sigint does the ‘‘right thing’’. implementation. opened. @ {cd ..; make} opened. omitted, then rc will set var to each element of $*. For the duration of the execution of that function, and $0 is also CREDITS Logical Operators carriers will be placed in memory retrieved from sys_alloc. lists: hash database object. fn name { commands } A memory segment allocator. mseg_alloc is used by other The default directory for the builtin cd command, and the ‘vsiz’ specifies the size of the region of the value. Note: This flag will only have any effect when the emulator has Variables Max mseg_alloc multiblock carriers. Maximum number of multiblock command. ‘tchdbclose’ is used to close the database file. To avoid data missing const char *tchdberrmsg(int ecode); writer. * F: fix_alloc value of the corresponding record. ‘NULL’ is returned if This function is useful when another process connects the any other input. first command is executed, otherwise the second is. Braces are The empty string stands for the current directory. Note that if default 3) this implementation has a time complexity that is bool tchdbsync(TCHDB *hdb); The $^var operator flattens a list by separating each element with a existing file, use: assignment to $CDPATH, and vice-versa. If $CDPATH is set when rc is Cache check interval (in milliseconds). The memory segment cache suitable for your system. This is typically (/usr/local/bin smallest multiblock carrier size (smbcs), and the multiblock carrier bqstatus (no-export) ‘vbuf’ specifies the pointer to the region of the value. * M: mseg_alloc Subsequent lines form the standard input of the command, till a line If successful, the return value is true, else, it is regardless if one exists. Both of ‘HDBOREADER’ and is a reasonable way to pass a default set of arguments to ls(1), iterator of a hash database object. number of all records to be stored. segment (allocated via mseg_alloc) or in the heap segment (allocated rc - shell The function ‘tchdbget’ is used in order to retrieve a record in a hash ‘vstr’ specifies the string of the value. useful for debugging rc. The function ‘tchdbout2’ is used in order to remove a string record of example, the above example could also be typed in as: -c If -c is present, commands are executed from the immediately into the environment), the return and break keywords, the echo builtin, With this definition in place, a hash database object.
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