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forks....HELP!!! someone anyone?
Post 49191 by richardspence2 on Saturday 27th of March 2004 02:36:03 PM
03-27-2004
forks!...more probs..HELP
Hey,
Having followed what you said, this is what I was able to create.
However, its not executing the commands thru the terminal. Please take a look at it and let me know what you think please.
****************************************************
#include <stdio.h>
main()
{
char buf[1024];
char *args[64];
for (;
{
/*
* Prompt for and read a command.
*/
printf("Command: ");
if (gets(buf) == NULL) {
printf("\n");
exit(0);
}
/*
* Split the string into arguments.
*/
parse(buf, args);
/*
* Execute the command.
*/
execute(args);
}
}
/*
* parse--split the command in buf into
* individual arguments.
*/
parse(buf, args)
char *buf;
char **args;
{
while (*buf != NULL) {
/*
* Strip whitespace
*/
while ((*buf == ' ') || (*buf == '\t'))
*buf++ = NULL;
/*
* Save the argument.
*/
*args++ = buf;
/*
* Skip over the argument.
*/
while ((*buf != NULL) && (*buf != ' ') && (*buf ! '\t'))
buf++;
}
*args = NULL;
}
/*
* execute--spawn a child process and execute
* the program.
*/
execute(args)
char **args;
{
int pid, status;
/*
* Get a child process.
*/
if ((pid = fork()) < 0) {
perror("fork");
exit(1);
}
/*
* The child executes the code inside the if.
*/
if (pid == 0) {
execvp(*args, args);
perror(*args);
exit(1);
}
/*
* The parent executes the wait.
*/
while (wait(&status) != pid)
/* empty */ ;
}
****************************************************
Thanks in advance
Having followed what you said, this is what I was able to create.
However, its not executing the commands thru the terminal. Please take a look at it and let me know what you think please.
****************************************************
#include <stdio.h>
main()
{
char buf[1024];
char *args[64];
for (;
{/*
* Prompt for and read a command.
*/
printf("Command: ");
if (gets(buf) == NULL) {
printf("\n");
exit(0);
}
/*
* Split the string into arguments.
*/
parse(buf, args);
/*
* Execute the command.
*/
execute(args);
}
}
/*
* parse--split the command in buf into
* individual arguments.
*/
parse(buf, args)
char *buf;
char **args;
{
while (*buf != NULL) {
/*
* Strip whitespace
*/
while ((*buf == ' ') || (*buf == '\t'))
*buf++ = NULL;
/*
* Save the argument.
*/
*args++ = buf;
/*
* Skip over the argument.
*/
while ((*buf != NULL) && (*buf != ' ') && (*buf ! '\t'))
buf++;
}
*args = NULL;
}
/*
* execute--spawn a child process and execute
* the program.
*/
execute(args)
char **args;
{
int pid, status;
/*
* Get a child process.
*/
if ((pid = fork()) < 0) {
perror("fork");
exit(1);
}
/*
* The child executes the code inside the if.
*/
if (pid == 0) {
execvp(*args, args);
perror(*args);
exit(1);
}
/*
* The parent executes the wait.
*/
while (wait(&status) != pid)
/* empty */ ;
}
****************************************************
Thanks in advance
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LEARN ABOUT SUSE
el
el(1) General Commands Manual el(1) NAME
el -- program to make a tuned shell-command for Oneliner SYNOPSIS
el [-acdfhioxV] [--command cmd] [--args n] [--format fmt] [--execute] [--inpipe buf] [--outpipe buf] [--serial] [--help] [--ver- sion] [--debug] DESCRIPTION
This manual page documents briefly the el command. This manual page was written for the Debian distribution because the original program does not have a manual page. Instead, it has docu- mentation in the GNU Info format; see below. el is a program that You can make a tuned shell-command for Oneliner with. This command can send S-exp to Emacs, and this can make Emacs evaluate it, too. In other words, you can execute Emacs's function from shell-commands. And you can make Emacs work in closer cooperation with your favorite shell-commands. OPTIONS
These programs follow the usual GNU command line syntax, with long options starting with two dashes (`-'). A summary of options is included below. For a complete description, see the Info files. -c cmd --command cmd cmd means a function of Elisp. Command line arguments and data from stdin means arguments of cmd. If you specify the only -c switch, el output one S-exp by one line of stdin. --a n --args n Specifies the maximum number of arguments of a Elisp function with -c switch. -f fmt --format fmt Allows you to use format string of printf for making a S-exp. -x --execute Requests to Oneliner to evaluate the S-exp to use *Oneliner auto-eval* buffer. -i buf --inpipe buf Gets input from pipe-buffer. You can specify a number of pipe-buffer, too. -o buf --outpipe buf Puts output to pipe-buffer. You can specify a number of pipe-buffer, too. -s --serial Makes el to serialize multiple lines to one line. -h --help Display help message. -V --version Display version identifiers. -d --debug Enable debugging state. SEE ALSO
The programs are documented fully by Oneliner(Shell-mode hooks for Oneliners) available via the Info system. AUTHOR
This manual page was written by OHURA Makoto <ohura@debian.org> for the Debian system (but may be used by others). Permission is granted to copy, distribute and/or modify this document under the terms of the GNU General Public License, Version 2 any later version published by the Free Software Foundation. On Debian systems, the complete text of the GNU General Public License can be found in /usr/share/common-licenses/GPL. el(1)