WORDEXP(3) BSD Library Functions Manual WORDEXP(3)
NAME
wordexp -- perform shell-style word expansions
SYNOPSIS
#include <wordexp.h>
int
wordexp(const char *restrict words, wordexp_t *restrict pwordexp, int flags);
void
wordfree(wordexp_t *pwordexp);
DESCRIPTION
The wordexp() function performs shell-style word expansion on words. It places the list of words into the we_wordv member of pwordexp and
the number of words into we_wordc.
The flags argument (see BUGS) is the bitwise inclusive OR of any of the following constants:
WRDE_APPEND Append the words to those generated by a previous call to wordexp().
WRDE_DOOFS As many NULL pointers as are specified by the we_offs member of pwordexp are added to the front of we_wordv.
WRDE_NOCMD Disallow command substitution in words. See the note in BUGS before using this.
WRDE_REUSE The pwordexp argument was passed to a previous successful call to wordexp() but has not been passed to wordfree(). The imple-
mentation may reuse the space allocated to it.
WRDE_SHOWERR Do not redirect shell error messages to /dev/null.
WRDE_UNDEF Report error on an attempt to expand an undefined shell variable.
The wordexp_t structure is defined in <wordexp.h> as:
typedef struct {
size_t we_wordc; /* count of words matched */
char **we_wordv; /* pointer to list of words */
size_t we_offs; /* slots to reserve in we_wordv */
} wordexp_t;
The wordfree() function frees the memory allocated by wordexp().
RETURN VALUES
The wordexp() function returns zero if successful, otherwise it returns one of the following error codes:
WRDE_BADCHAR The words argument contains one of the following unquoted characters: <newline>, '|', '&', ';', '<', '>', '(', ')', '{', '}'.
WRDE_BADVAL An attempt was made to expand an undefined shell variable and WRDE_UNDEF is set in flags.
WRDE_CMDSUB An attempt was made to use command substitution and WRDE_NOCMD is set in flags.
WRDE_NOSPACE Not enough memory to store the result.
WRDE_SYNTAX Shell syntax error in words.
The wordfree() function returns no value.
EXAMPLES
Invoke the editor on all .c files in the current directory and /etc/motd (error checking omitted):
wordexp_t pwordexp;
wordexp("${EDITOR:-vi} *.c /etc/motd", &pwordexp, 0);
execvp(pwordexp->we_wordv[0], pwordexp->we_wordv);
SEE ALSO
sh(1), fnmatch(3), glob(3), popen(3), system(3)
BUGS
This version of wordexp() ignores the value of the flags argument.
COPYRIGHT
Copyright 1995-2002 University Corporation for Atmospheric Research/Unidata
Portions of this software were developed by the Unidata Program at the University Corporation for Atmospheric Research.
BSD
December 27, 2002 BSD