NAME

wordexp.h - word-expansion types

SYNOPSIS

#include <wordexp.h>

DESCRIPTION

The <wordexp.h> header shall define the structures and symbolic constants used by the wordexp() and wordfree() functions.

The structure type wordexp_t shall contain at least the following members:

size_t   we_wordc  Count of words matched by words. 
char   **we_wordv  Pointer to list of expanded words. 
size_t   we_offs   Slots to reserve at the beginning of we_wordv. 

The flags argument to the wordexp() function shall be the bitwise-inclusive OR of the following flags:

WRDE_APPEND

Append words to those previously generated.

WRDE_DOOFFS

Number of null pointers to prepend to we_wordv.

WRDE_NOCMD

Fail if command substitution is requested.

WRDE_REUSE

The pwordexp argument was passed to a previous successful call to wordexp(), and has not been passed to wordfree(). The result is the same as if the application had called wordfree() and then called wordexp() without WRDE_REUSE.

WRDE_SHOWERR

Do not redirect stderr to /dev/null.

WRDE_UNDEF

Report error on an attempt to expand an undefined shell variable.

The following constants shall be defined as error return values:

WRDE_BADCHAR

One of the unquoted characters- <newline>, '|', '&', ';', '<', '>', '(', ')', '{', '}' - appears in words in an inappropriate context.

WRDE_BADVAL

Reference to undefined shell variable when WRDE_UNDEF is set in flags.

WRDE_CMDSUB

Command substitution requested when WRDE_NOCMD was set in flags.

WRDE_NOSPACE

Attempt to allocate memory failed.

WRDE_NOSYS

^{[OB XSI]} Reserved.

WRDE_SYNTAX

Shell syntax error, such as unbalanced parentheses or unterminated string.

The <wordexp.h> header shall define the following type:

size_t

^[XSI] As described in <stddef.h>.

The following shall be declared as functions and may also be defined as macros. Function prototypes shall be provided.

int  wordexp(const char *restrict, wordexp_t *restrict, int);
void wordfree(wordexp_t *);

The implementation may define additional macros or constants using names beginning with WRDE_.

APPLICATION USAGE

None.

RATIONALE

None.

FUTURE DIRECTIONS

None.

SEE ALSO

<stddef.h>, the System Interfaces volume of IEEE Std 1003.1-2001, wordexp(), the Shell and Utilities volume of IEEE Std 1003.1-2001

CHANGE HISTORY

First released in Issue 4. Derived from the ISO POSIX-2 standard.

Issue 6

The restrict keyword is added to the prototype for wordexp().

The WRDE_NOSYS constant is marked obsolescent.