I figured out where the problem lies. "scd" is the script that I'm tring to run, and I'm in my home directory and enter:
I get:
Then I do pwd and get:
When the program encounters "cd ${1:-`pwd}" it changes the directory for the script but doesn't stay there. So when i type my cmmand with no argument it does what I expect it to and defaults to the current directory.
If I in root ( / ) and type:
I get:
Could this just be an anomoly?
I know this script is crummy, but I was just messing around.. how do I get sed's insert command to allow variable expansion to show the filename?
#!/bin/bash
filename=`echo $0`
/usr/bin/sed '/#include/ {
i\
the filename is `$filename`
}' $1
exit 0 (8 Replies)
When script is running you only see when some of the commands are not successfull.
Is there a way to see which command are executed and to show the substitution of variables as every line is executed ? (3 Replies)
For example I have variable like below
echo $OUTPUT
/some/path/`uname -n`
when I try to use the variable OUTPUT like below
cd $OUTPUT or cd ${OUTPUT}
I am getting bad substituion error message
$ cd $OUTPUT
ksh: cd: bad substitution
$ cd ${OUTPUT}
ksh: cd: bad substitution
... (1 Reply)
Hi Jim,
The following script is in working state. But i m having one more problem with awk cmd. Could you tell me how to use any variable inside awk or how to take any variable value outside awk.
My problem is i want to maintain one property file in which i am declaring variable value into that... (12 Replies)
Hi,
I am trying to do the following thing
var='date'
$var
Above command substitutes date for and in turn runs the date command and i am getting the todays date value.
I am trying to do the same thing as following, but facing some problems,
unique_host_pro="sed -e ' /#/d'... (3 Replies)
Hello All,
I don't write scripts very often, and in this case I am stumped, although it may be a bug in the version of bash I have to use (it's not my system).
I want to extract a specific string snippet from a block of text (coming from a log file) that is dependent on a bunch of other... (1 Reply)
Hello people.
Part of my script:
SUBSETID=`echo $PMFILE |sed 's/pmresult_//' | sed 's/_*//'`
MAPFILE=`find /huawei/cell /huawei/nodeb /huawei/rnc -name 'mapping_$SUBSETID.txt' |grep -v backup`
Unfortunatelly variable $SUBSETID in the MAPFILE declaration will not return the... (3 Replies)
If I execute the following line of code:
echo "*"
I get a list of files in the current directory.
What if all I wanted to do was display the asterisk itself? What does the code have to look like so all I get is an asterisk?
Thanks ahead of time for your assistance
----------... (3 Replies)
Is it possible to store a command inside a variable?
i want this piece to be stored inside a variable, so i can use it later in a different command
$u | cut -d " " -f 2
var="$u | cut -d " " -f 2"
eval $var
I tried to use eval but I receive this error:
-f 2: command not found
... (5 Replies)
Hi, I am new in scripting, and I am currently working on a script that will look for other files in a certain directory and exclude some file type.
this works fine:Find_File2Exclude=`find ${paths} -maxdepth 1 -type f \( ! -iname '*.out' ! -iname '*.auc' ! -iname '*.cps' ! -iname '*.log' ! -iname... (4 Replies)
Discussion started by: kedd05
4 Replies
LEARN ABOUT LINUX
wordfree
WORDEXP(3) Linux Programmer's Manual WORDEXP(3)NAME
wordexp, wordfree - perform word expansion like a posix-shell
SYNOPSIS
#include <wordexp.h>
int wordexp(const char *s, wordexp_t *p, int flags);
void wordfree(wordexp_t *p);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
wordexp(), wordfree(): _XOPEN_SOURCE
DESCRIPTION
The function wordexp() performs a shell-like expansion of the string s and returns the result in the structure pointed to by p. The data
type wordexp_t is a structure that at least has the fields we_wordc, we_wordv, and we_offs. The field we_wordc is a size_t that gives the
number of words in the expansion of s. The field we_wordv is a char ** that points to the array of words found. The field we_offs of type
size_t is sometimes (depending on flags, see below) used to indicate the number of initial elements in the we_wordv array that should be
filled with NULLs.
The function wordfree() frees the allocated memory again. More precisely, it does not free its argument, but it frees the array we_wordv
and the strings that points to.
The string argument
Since the expansion is the same as the expansion by the shell (see sh(1)) of the parameters to a command, the string s must not contain
characters that would be illegal in shell command parameters. In particular, there must not be any unescaped newline or |, &, ;, <, >, (,
), {, } characters outside a command substitution or parameter substitution context.
If the argument s contains a word that starts with an unquoted comment character #, then it is unspecified whether that word and all fol-
lowing words are ignored, or the # is treated as a non-comment character.
The expansion
The expansion done consists of the following stages: tilde expansion (replacing ~user by user's home directory), variable substitution
(replacing $FOO by the value of the environment variable FOO), command substitution (replacing $(command) or `command` by the output of
command), arithmetic expansion, field splitting, wildcard expansion, quote removal.
The result of expansion of special parameters ($@, $*, $#, $?, $-, $$, $!, $0) is unspecified.
Field splitting is done using the environment variable $IFS. If it is not set, the field separators are space, tab and newline.
The output array
The array we_wordv contains the words found, followed by a NULL.
The flags argument
The flag argument is a bitwise inclusive OR of the following values:
WRDE_APPEND
Append the words found to the array resulting from a previous call.
WRDE_DOOFFS
Insert we_offs initial NULLs in the array we_wordv. (These are not counted in the returned we_wordc.)
WRDE_NOCMD
Don't do command substitution.
WRDE_REUSE
The argument p resulted from a previous call to wordexp(), and wordfree() was not called. Reuse the allocated storage.
WRDE_SHOWERR
Normally during command substitution stderr is redirected to /dev/null. This flag specifies that stderr is not to be redirected.
WRDE_UNDEF
Consider it an error if an undefined shell variable is expanded.
RETURN VALUE
In case of success 0 is returned. In case of error one of the following five values is returned.
WRDE_BADCHAR
Illegal occurrence of newline or one of |, &, ;, <, >, (, ), {, }.
WRDE_BADVAL
An undefined shell variable was referenced, and the WRDE_UNDEF flag told us to consider this an error.
WRDE_CMDSUB
Command substitution occurred, and the WRDE_NOCMD flag told us to consider this an error.
WRDE_NOSPACE
Out of memory.
WRDE_SYNTAX
Shell syntax error, such as unbalanced parentheses or unmatched quotes.
VERSIONS
wordexp() and wordfree() are provided in glibc since version 2.1.
CONFORMING TO
POSIX.1-2001.
EXAMPLE
The output of the following example program is approximately that of "ls [a-c]*.c".
#include <stdio.h>
#include <stdlib.h>
#include <wordexp.h>
int
main(int argc, char **argv)
{
wordexp_t p;
char **w;
int i;
wordexp("[a-c]*.c", &p, 0);
w = p.we_wordv;
for (i = 0; i < p.we_wordc; i++)
printf("%s
", w[i]);
wordfree(&p);
exit(EXIT_SUCCESS);
}
SEE ALSO fnmatch(3), glob(3)COLOPHON
This page is part of release 3.27 of the Linux man-pages project. A description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
2008-07-14 WORDEXP(3)