| /* |
| * Copyright (C) Bull S.A. 1996 |
| * Copyright (c) International Business Machines Corp., 2001 |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See |
| * the GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| */ |
| /*---------------------------------------------------------------------+ |
| | message_queue_test_02_snd | |
| | ==================================================================== | |
| | | |
| | Description: Create a message queue to send messages between two | |
| | processes. | |
| | | |
| | Algorithm: o Generate a key value given the project name and id | |
| | | |
| | o Get a unique message queue id | |
| | | |
| | o Print out message queue id | |
| | | |
| | System calls: The following system calls are made | |
| | | |
| | o ftok () - generates a standard IPC key | |
| | o msgget () - gets a message queue identifier | |
| | | |
| | Usage: message_queue_test_02_snd [-f file] [-i id] | |
| | [-m msg | -b bytes] | |
| | | |
| | To compile: cc -o message_queue_test_02_snd \ | |
| | message_queue_test_02_snd.c | |
| | | |
| | Last update: Ver. 1.2, 2/26/94 14:03:51 | |
| | | |
| | Change Activity | |
| | | |
| | Version Date Name Reason | |
| | 0.1 032789 CST Initial version | |
| | 1.2 111993 DJK Modify for AIX version 4.1 | |
| | 1.3 022694 DJK Moved to Prod directory | |
| | | |
| +---------------------------------------------------------------------*/ |
| |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <stdio.h> |
| #include <unistd.h> |
| #include <sys/ipc.h> |
| #ifdef _LINUX_ |
| # include <sys/stat.h> |
| // defines struct msgbuf |
| # define __USE_GNU |
| #endif |
| #include <sys/msg.h> |
| #include <sys/types.h> |
| #include <string.h> |
| #include <stdlib.h> |
| |
| /* |
| * Defines |
| * |
| * BUF_SIZE: size of message buffer... |
| */ |
| #define BUF_SIZE 256 |
| #define DEFAULT_MESSAGE "<< Message Queue test default message >>" |
| //#define DEFAULT_MESSAGE "" |
| #define DEFAULT_PROJECT_NAME "/tmp/message_queue_test" |
| #define DEFAULT_PROJECT_ID 20 |
| #define USAGE "\nUsage: %s [-f project_name ] [-i project_id ] \n" \ |
| " {-m msg | -b bytes} \n\n" |
| |
| /* |
| * Function prototypes |
| * |
| * parse_args (): Parse command line arguments |
| * sys_error (): System error message function |
| * error (): Error message function |
| */ |
| static void parse_args (int, char **); |
| static void sys_error (const char *, int); |
| static void error (const char *, int); |
| |
| /* |
| * Global variables |
| * |
| * message: Message to store in queue |
| * project_name: Unique path used to create key (ftok) |
| * project_id: Unique number used to create key (ftok) |
| */ |
| size_t bytes = 0; |
| char *message = DEFAULT_MESSAGE; |
| char *project_name = DEFAULT_PROJECT_NAME; |
| char project_id = DEFAULT_PROJECT_ID; |
| |
| /*---------------------------------------------------------------------+ |
| | main | |
| | ==================================================================== | |
| | | |
| | Function: Main program (see prolog for more details) | |
| | | |
| | Returns: (0) Successful completion | |
| | (-1) Error occurred | |
| | | |
| +---------------------------------------------------------------------*/ |
| int main (int argc, char **argv) |
| { |
| struct msgbuf *buf; /* Message buffer */ |
| key_t key; /* Unique key */ |
| int msqid; /* Message queue identifier */ |
| size_t size; /* Size of message buffer */ |
| |
| /* |
| * Parse command line options |
| */ |
| parse_args (argc, argv); |
| |
| if ((key = ftok (project_name, project_id)) < 0) |
| sys_error ("ftok failed", __LINE__); |
| |
| if ((msqid = msgget (key, S_IRUSR|S_IWUSR)) < 0) |
| sys_error ("msgget failed", __LINE__); |
| |
| if (bytes) { |
| buf = (struct msgbuf *) calloc (bytes + sizeof(struct msgbuf), |
| sizeof (char)); |
| buf->mtype = 1L; |
| |
| if (msgsnd (msqid, buf, bytes, 0) < 0) |
| sys_error ("msgsnd failed", __LINE__); |
| |
| free (buf); |
| |
| } else { |
| size = strlen (message) + 1; |
| buf = (struct msgbuf *) calloc (size + sizeof(struct msgbuf), |
| sizeof (char)); |
| |
| buf->mtype = 1L; |
| strcpy (buf->mtext, message); |
| |
| if (msgsnd (msqid, buf, size, 0) < 0) |
| sys_error ("msgsnd failed", __LINE__); |
| |
| free (buf); |
| } |
| |
| return (0); |
| } |
| |
| /*---------------------------------------------------------------------+ |
| | parse_args () | |
| | ==================================================================== | |
| | | |
| | Function: Parse the command line arguments & initialize global | |
| | variables. | |
| | | |
| | Updates: (command line options) | |
| | | |
| | [-f] file: project file | |
| | | |
| | [-i] num: project id | |
| | | |
| | [-m] msg: message to transmit | |
| | | |
| | [-b] byes: number of bytes to send | |
| | | |
| +---------------------------------------------------------------------*/ |
| static void parse_args (int argc, char **argv) |
| { |
| int opt; |
| int errflag = 0; |
| char *program_name = *argv; |
| extern char *optarg; /* Command line option */ |
| |
| /* |
| * Parse command line options. |
| */ |
| while ((opt = getopt(argc, argv, "b:m:f:i:")) != EOF) { |
| switch (opt) { |
| case 'b': /* number of bytes to send */ |
| bytes = atoi (optarg); |
| break; |
| case 'm': /* message to send */ |
| message = optarg; |
| break; |
| case 'f': /* project file */ |
| project_name = optarg; |
| break; |
| case 'i': /* project id */ |
| project_id = *optarg; |
| break; |
| default: |
| errflag++; |
| break; |
| } |
| } |
| if (errflag) { |
| fprintf (stderr, USAGE, program_name); |
| exit (2); |
| } |
| } |
| |
| /*---------------------------------------------------------------------+ |
| | sys_error () | |
| | ==================================================================== | |
| | | |
| | Function: Creates system error message and calls error () | |
| | | |
| +---------------------------------------------------------------------*/ |
| static void sys_error (const char *msg, int line) |
| { |
| char syserr_msg [256]; |
| |
| sprintf (syserr_msg, "%s: %s\n", msg, strerror (errno)); |
| error (syserr_msg, line); |
| } |
| |
| /*---------------------------------------------------------------------+ |
| | error () | |
| | ==================================================================== | |
| | | |
| | Function: Prints out message and exits... | |
| | | |
| +---------------------------------------------------------------------*/ |
| static void error (const char *msg, int line) |
| { |
| fprintf (stderr, "ERROR [line: %d] %s\n", line, msg); |
| exit (-1); |
| } |