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| SIGOPER |
| Updates to Header Files in Function Examples |
In Chapter 20, "POSIX Function Reference," replace the examples
for the chpriority, getpgid, and getsid functions with
the examples that are provided here.
/*---------------------------+
| POSIX/UNIX header files |
+----------------------------*/
#include <sys/types.h>
#include <unistd.h>
#include <sys/resource.h>
/*---------------------------+
| ISO/ANSI header files |
+----------------------------*/
#include <stdio.h>
#include <stdlib.h>
/*---------------------------+
| Name: main |
| Returns: exit(EXIT_SUCCESS)|
| or exit(EXIT_FAILURE) |
+----------------------------|
+---------------------------*/
int main()
{
/* generic return code */
int rc;
/* which kind of process */
/* id to use */
int kind;
/* process id */
pid_t id;
/* is oeprty relative or */
/* absolute */
int form;
/* process priority */
/* (version 1) */
int prty1;
/* process priority */
/* (version 2) */
int prty2;
/* process id from getpid() */
pid_t pid;
/* process group id from */
/* getpgid() */
pid_t pgid;
/* process user id from */
/* getuid() */
uid_t uid;
/* get the user id for this */
/* process */
uid = getuid();
/* get the process id for */
/* this process */
pid = getpid();
/* get the group process id */
/* for this process */
pgid = getpgid(pid);
if (pgid == -1)
{
perror("Call to getpgid failed");
exit(EXIT_FAILURE);
}
printf(" The process id: %d\n",
(int)pid);
printf("The process group id: %d\n",
(int)pgid);
printf(" The process user id: %d\n",
(int)uid);
/*------------------------------*/
/* Get the process priority */
/* using the process id */
/*------------------------------*/
printf("\nGet the Process Priority using the Process ID\n");
/* the id arg is the pid of a process */
kind = PRIO_PROCESS;
/* version 1 */
id = (id_t)pid;
/* Set errno to zero for */
/* error handling */
errno = 0;
prty1 = getpriority(kind, id);
/* ---------------------------------*/
/* Test for Error */
/* Note: */
/* getpriority() may return a '-1' */
/* return code for either a */
/* failure rc, or when the priority */
/* is in-fact '-1'. To distinguish */
/* between the two conditions, */
/* check the errno */
/* value for a non-zero value. */
/*----------------------------------*/
if (prty1 == -1 && errno != 0)
{
perror("Call to getpriority failed");
exit(EXIT_FAILURE);
}
else
{
printf("The process priority (pid:version 1): %d\n", prty1);
}
/* version 2 */
/* 0 implies current processs id */
id = (id_t)0;
/* Reset errno to zero for */
/* error handling */
errno = 0;
prty2 = getpriority(kind, id);
/* Test for Error */
if (prty2 == -1 && errno != 0)
{
perror("Call to getpriority failed");
exit(EXIT_FAILURE);
}
else
{
printf("The process priority (pid:version 2): %d\n", prty2);
}
/*-----------------------------*/
/* Get the process priority */
/* using the group process id */
/*-----------------------------*/
printf("\nGet the Process Priority using the Group Process ID\n");
/* the id arg is the group process id */
kind = PRIO_PGRP;
/* version 1 */
id = (id_t)pgid;
/* Set errno to zero for error handling */
errno = 0;
prty1 = getpriority(kind, id);
/* Test for Error */
if (prty1 == -1 && errno != 0)
{
perror("Call to getpriority failed");
exit(EXIT_FAILURE);
}
else
{
printf("The process priority (gpid:version 1): %d\n", prty1);
}
/* version 2 */
/* 0 implies current group processs id */
id = (id_t)0;
/* Reset errno to zero for error handling */
errno = 0;
prty2 = getpriority(kind, id);
/* Test for Error */
if (prty2 == -1 && errno != 0)
{
perror("Call to getpriority failed");
exit(EXIT_FAILURE);
}
else
{
printf("The process priority (gpid:version 2): %d\n", prty2);
}
/*-------------------------------------------*/
/* Get the process priority using the */
/* process User id */
/*-------------------------------------------*/
printf("\nGet the Process Priority of the User ID\n");
/* the id arg is the user id of the process */
kind = PRIO_USER;
/* version 1 */
id = (id_t)uid;
/* Set errno to zero for error handling */
errno = 0;
prty1 = getpriority(kind, id);
/* Test for Error */
if (prty1 == -1 && errno != 0)
{
perror("Call to getpriority failed");
exit(EXIT_FAILURE);
}
else
{
printf("The process priority (uid:version 2): %d\n", prty1);
}
/* version 2 */
/* Reset errno to zero for error handling */
errno = 0;
/* 0 implies current process user id */
id = (id_t)0;
prty2 = getpriority(kind, id);
/* Test for Error */
if (prty2 == -1 && errno != 0)
{
perror("Call to getpriority failed");
exit(EXIT_FAILURE);
}
else
{
printf("The process priority (uid:version 2): %d\n", prty2);
}
/*-----------------------------------------------*/
/* Set the process priority using the */
/* process id */
/*----------------------------------------------*/
printf("\nSet the Process Priority using the Process ID\n");
/* the id arg is the pid of a process */
kind = PRIO_PROCESS;
/* an id of 0 implies current processs id */
id = (id_t)0;
/* Reset errno to zero for error handling */
errno = 0;
/* Set process priority to 5 */
prty1 = 5;
rc = setpriority(kind, id, prty1);
/*------------------------------------------------*/
/* Test for Error */
/* Note: UNIX System Services sites must enable */
/* the use of the setpriority() function. */
/* If the use of setpriority() has not */
/* beenenabled, any use of setpriority() */
/* will fail with errno set to ENOSYS. */
/* */
/*------------------------------------------------*/
if (rc == -1)
{
perror("Call to setpriority failed");
exit(EXIT_FAILURE);
}
else
{
prty2 = getpriority(kind, id);
/* Test for Error */
if (errno != 0)
{
perror("Call to getpriority failed");
exit(EXIT_FAILURE);
}
printf("The process priority is now (pid): %d\n", prty2);
}
/*--------------------------------------------*/
/* Set the process priority using the group */
/* process id */
/*--------------------------------------------*/
printf("\nSet the Process Priority using the Group Process ID\n");
/* the id arg is the group id of the process */
kind = PRIO_PGRP;
/* 0 implies current group processs id */
id = (id_t)0;
/* Reset errno to zero for error handling */
errno = 0;
/* Set process priority to 10 */
prty1 = 10;
rc = setpriority(kind, id, prty1);
/* Test for Error */
if (rc == -1)
{
perror("Call to setpriority failed");
exit(EXIT_FAILURE);
}
else
{
prty2 = getpriority(kind, id);
/* Test for Error */
if (errno != 0)
{
perror("Call to getpriority failed");
exit(EXIT_FAILURE);
}
printf("The process priority is now (gpid): %d\n", prty2);
}
/*-------------------------------------------*/
/* Set the process priority using the */
/*process User id */
/*-------------------------------------------*/
printf("\nSet the Process Priority of the User ID\n");
/* the id arg is the user id of the process */
kind = PRIO_USER;
/* an id of 0 implies current user id */
id = (id_t)0;
/* Reset errno to zero for error handling */
errno = 0;
/* Set process priority to 15 */
prty1 = 15;
rc = setpriority(kind, id, prty1);
/* Test for Error */
if (rc == -1)
{
perror("Call to setpriority failed");
exit(EXIT_FAILURE);
}
else
{
prty2 = getpriority(kind, id);
/* Test for Error */
if (errno != 0)
{
perror("Call to getpriority failed");
exit(EXIT_FAILURE);
}
printf("The process priority is now (uid): %d\n", prty2);
}
/*-------------------------------------------*/
/* Change the process priority using the */
/* process id */
/*-------------------------------------------*/
printf("\nChange the Process Priority using the Process ID\n");
/* the id arg is the pid of a process */
kind = PRIO_PROCESS;
/* an id of 0 implies current processs id */
id = (id_t)0;
/* Reset errno to zero for error handling */
errno = 0;
/* change using "absolute" */
/* priority - equivalent to setpriority() */
form = CPRIO_ABSOLUTE;
printf("\tChange using CPRIO_ABSOLUTE\n");
/* Change process priority to 3 */
prty1 = 3;
rc = chpriority(kind, id, form, prty1);
/*------------------------------------------------*/
/* Test for Error */
/* Note: UNIX System Services sites must enable */
/* the use of the chpriority() function. */
/* If the use of chpriority() has not been */
/* enabled, any use of chpriority() will */
/* fail with errno set to ENOSYS. */
/* */
/*------------------------------------------------*/
if (rc == -1)
{
perror("Call to chpriority failed");
exit(EXIT_FAILURE);
}
else
{
prty2 = getpriority(kind, id);
/* Test for Error */
if (errno != 0)
{
perror("Call to getpriority failed");
exit(EXIT_FAILURE);
}
printf("The process priority is now (pid): %d\n", prty2);
}
/* change using "relative" priority */
form = CPRIO_RELATIVE;
printf("\tChange using CPRIO_RELATIVE\n");
/* Bump process priority up by 2 */
prty1 = 2;
rc = chpriority(kind, id, form, prty1);
/* Test for Error */
if (rc == -1)
{
perror("Call to chpriority failed");
exit(EXIT_FAILURE);
}
else
{
prty2 = getpriority(kind, id);
/* Test for Error */
if (errno != 0)
{
perror("Call to getpriority failed");
exit(EXIT_FAILURE);
}
printf("The process priority is now (pid): %d\n", prty2);
}
/*---------------------------------------------*/
/* Change the process priority using the */
/* group process id */
/*---------------------------------------------*/
printf("\nChange the Process Priority using the Group Process ID\n");
/* the id arg is the group id of the process */
kind = PRIO_PGRP;
/* 0 implies current group processs id */
id = (id_t)0;
/* Reset errno to zero for error handling */
errno = 0;
/* change using "absolute" */
/* priority - equivalent to setpriority() */
form = CPRIO_ABSOLUTE;
printf("\tChange using CPRIO_ABSOLUTE\n");
/* Change process priority to 7 */
prty1 = 7;
rc = chpriority(kind, id, form, prty1);
/* Test for Error */
if (rc == -1)
{
perror("Call to chpriority failed");
exit(EXIT_FAILURE);
}
else
{
prty2 = getpriority(kind, id);
/* Test for Error */
if (errno != 0)
{
perror("Call to getpriority failed");
exit(EXIT_FAILURE);
}
printf("The process priority is now (gpid): %d\n", prty2);
}
/* change using "relative" priority */
form = CPRIO_RELATIVE;
printf("\tChange using CPRIO_RELATIVE\n");
/* Bump process priority up by 3 */
prty1 = 3;
rc = chpriority(kind, id, form, prty1);
/* Test for Error */
if (rc == -1)
{
perror("Call to chpriority failed");
exit(EXIT_FAILURE);
}
else
{
prty2 = getpriority(kind, id);
/* Test for Error */
if (errno != 0)
{
perror("Call to getpriority failed");
exit(EXIT_FAILURE);
}
printf("The process priority is now (gpid): %d\n", prty2);
}
/*--------------------------------------*/
/* Change the process priority using */
/* the process User id */
/*--------------------------------------*/
printf("\nChange the Process Priority of the User ID\n");
/* the id arg is the user id of the process */
kind = PRIO_USER;
/* 0 implies current group processs id */
id = (id_t)0;
/* Reset errno to zero for error handling */
errno = 0;
/* change using "absolute" */
/* priority - equivalent to setpriority() */
form = CPRIO_ABSOLUTE;
printf("\tChange using CPRIO_ABSOLUTE\n");
/* Change process priority to 11 */
prty1 = 11;
rc = chpriority(kind, id, form, prty1);
/* Test for Error */
if (rc == -1)
{
perror("Call to chpriority failed");
exit(EXIT_FAILURE);
}
else
{
prty2 = getpriority(kind, id);
/* Test for Error */
if (errno != 0)
{
perror("Call to getpriority failed");
exit(EXIT_FAILURE);
}
printf("The process priority is now (uid): %d\n", prty2);
}
/* change using "relative" priority */
form = CPRIO_RELATIVE;
printf("\tChange using CPRIO_RELATIVE\n");
/* Bump process priority up by 4 */
prty1 = 4;
rc = chpriority(kind, id, form, prty1);
/* Test for Error */
if (rc == -1)
{
perror("Call to chpriority failed");
exit(EXIT_FAILURE);
}
else
{
prty2 = getpriority(kind, id);
/* Test for Error */
if (errno != 0)
{
perror("Call to getpriority failed");
exit(EXIT_FAILURE);
}
printf("The process priority is now (uid): %d\n", prty2);
}
exit(EXIT_SUCCESS);
} /* end of main() */
/*------------------------------------+
| POSIX/UNIX header files |
+-------------------------------------*/
#include <sys/types.h>
#include <unistd.h>
/*------------------------------------+
| ISO/ANSI header files |
+-------------------------------------*/
#include <stdio.h>
#include <stdlib.h>
/*------------------------------------+
| Name: main |
| Returns: exit(EXIT_SUCCESS) or
| exit(EXIT_FAILURE) |
+-------------------------------------*/
int main()
{
/* current process id from getpid() */
pid_t pid;
/* process group id from getpgid() */
pid_t pgid;
/*------------------------------------------*/
/* Get the group process id of the current */
/* process */
/* Note: Both version 1 and version 2 are */
/* equivalent to calling the */
/* getpgrp() function */
/*------------------------------------------*/
printf("\nGet the Group Process ID of the Current Process\n");
/* version 1 */
/* Set errno to zero for error handling */
errno = 0;
/* get the process id for this process */
pid = getpid();
/* get the group process id for this process */
pgid = getpgid(pid);
/* Test for Error */
if (pgid == -1)
{
perror("Call to getpgid failed");
exit(EXIT_FAILURE);
}
else
{
printf(" The process id: %d\n", (int)pid);
printf("The process group id:%d\n", (int)pgid);
}
/* version 2 */
/* Reset errno to zero for error handling */
errno = 0;
/* 0 implies current processs id */
pid = 0;
/* get the group process id for this process */
pgid = getpgid(pid);
/* Test for Error */
if (pgid == -1)
{
perror("Call to getpgid failed");
exit(EXIT_FAILURE);
}
else
{
printf("The process group id: %d\n", (int)pgid);
}
exit(EXIT_SUCCESS);
} /* end of main() */
/*------------------------------------+
| POSIX/UNIX header files |
+-------------------------------------*/
#include <sys/types.h>
#include <unistd.h>
/*------------------------------------+
| ISO/ANSI header files |
+-------------------------------------*/
#include <stdio.h>
#include <stdlib.h>
/*--------------------------------------+
| Name: main |
| Returns: exit(EXIT_SUCCESS) |
| or exit(EXIT_FAILURE) |
+ -------------------------------------*/
int main()
{
/* current process id from getpid() */
pid_t pid;
/* process group id from getsid() */
pid_t sid;
/*---------------------------------------*/
/* Get the Session Leader id for the */
/* Current Process */
/*---------------------------------------*/
printf("\nGet the Session Leader ID of the Current Process\n");
/* version 1 */
/* Set errno to zero for error handling */
errno = 0;
/* get the process id for this process */
pid = getpid();
/* get the session leader id for */
/* this process */
sid = getsid(pid);
/* Test for Error */
if (sid == -1)
{
perror("Call to getsid failed");
exit(EXIT_FAILURE);
}
else
{
printf(" The process id: %d\n", (int)pid);
printf("The Session Leader id: %d\n", (int)sid);
}
/* version 2 */
/* Reset errno to zero for error handling */
errno = 0;
/* 0 implies current processs id */
pid = 0;
/* get the session leader id for */
/* this process */
sid = getsid(pid);
/* Test for Error */
if (sid == -1)
{
perror("Call to getsid failed");
exit(EXIT_FAILURE);
}
else
{
printf(" The process id: %d\n",
(int)pid);
printf("The Session Leader id: %d\n",
(int)sid);
}
exit(EXIT_SUCCESS);
} /* end of main() */
Replace the #include statements in the chown example with the
#include
statements that are provided here.
#include <sys/types.h> #include <grp.h> #include <stdlib.h> #include <stdio.h> #include <unistd.h>
| New oeattach Example |
In Chapter 20, "POSIX Function Reference," replace the oeattach sample code under the
"Example" heading
with the following code:
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <stdio.h>
#include <signal.h>
#include <lclib.h>
main()
{
int pipefds[2];
pid_t pid;
char *const parmList[] = {"/bin/ls", "-l", "/u/userid/dirname",
NULL };
char lsout[200]; /* buffer for out ls output */
int amt;
int status; /* status code from ls */
fclose(stdout); /* avoid stdio interfering with fd 1 */
fclose(stdin); /* avoid stdio interfering with fd 0 */
close(STDOUT_FILENO); /* make sure fd's 0 & 1 are avail */
close(STDIN_FILENO);
pipe(pipefds); /* create both ends of a pipe */
if (pipefds[0] == STDOUT_FILENO) {
fprintf(stderr,
"Warning: Input fileno is 1, should not occur.\n");
pipefds[0] = dup(pipefds[0]);
close(STDOUT_FILENO);
}
if (pipefds[1] != STDOUT_FILENO) {
fprintf(stderr,
"Warning: Output fileno is not 1, should not occur.\n");
dup2(pipefds[1],STDOUT_FILENO);
/* make write end of pipe fd 1 */
close(pipefds[1]); /* close write end */
}
pid = oeattach("/bin/ls", parmList);
/* run ls command as subtask */
close(STDOUT_FILENO); /* close write end of pipe in parent */
for(;;) { /* read from the pipe */
amt = read(pipefds[0], lsout, sizeof(lsout));
if (amt <= 0) break;
fwrite(lsout, 1, amt, stderr); /* write ls output to stderr */
}
wait(&status); /* wait for ls to complete */
close(pipefds[0]); /* close pipe input end */
if (WIFEXITED(status)) exit(WEXITSTATUS(status));
else /* if ls failed, use kill to fail the same way */
kill(0, WTERMSIG(status));
}
| Update to loadm Function Description |
In Chapter 1, "Dynamic-Loading Functions," in the loadm function
description, in the section titled, "Example
1.2 dynamic loading modules with multiple functions," replace the example
code in "STEP I. Put the following declarations a common header file
and name it DYNTABLE:" with the following example:
int func1(void)
int func2(void)
struct funcdef { /* structure definition for functions */
int (*func1)();
int (*func2)();
/* More functions can go here. */
};
typedef struct funcdef *fptrtable; /* pointer to list of funcdefs */
| Updates to the osdynalloc Function |
In Chapter 3, "MVS Low-Level I/O Functions," update the osdynalloc function
description with the following information.
Replace the corresponding lines in the table labeled, "SVC 99 Request Block Keywords," with the following entries:
| Identifier | RB Field | Value | Description | Notes |
|---|---|---|---|---|
| msgbelowelsto | S99LSTO | none | Allocate SVC 99 messages below the 16 meg line | |
| msgerrormsgrc | none | int* | Message processing error code (returned in register 15 by IEFDB476) |
Replace the corresponding lines in the table labeled, "Dynamic Allocation Keywords," with the following entries:
| Identifier | JCL Equiv | SVC 99Key | Value | Format | Description | Notes |
|---|---|---|---|---|---|---|
| subsysattrssattrssatt | none | DALSSATT | char* | Res Word | Subsystem attributes | (6) |
| subsysparmssparmssprm | SUBSYS= (,parm... ) | DALSSPRM | char[68] | Multiple | Subsystem Parameters | (4) |
Add the following lines to the table labeled, "Dynamic Allocation Keywords:"
| Identifier | JCL Equiv | SVC 99Key | Value | Format | Description | Notes |
|---|---|---|---|---|---|---|
| buflbuflenbuflndcbbufldcbbuflendcbbufln | DCB=BUFL= | DALBUFL | int | Buffer length | ||
| fdatfiledata | FILEDATA= | DALFDAT | char* | Res Word | TEXT/BINARY for HFS file | |
| ovaffoveraffoverrideaff | DALOVAFF | none | Override affinity | |||
| retclienttokretctkrtctokenrtctkrtctoken | none | DALRTCTK | char(*) | [81] | Return JES client token | |
| ssreq | none | DALSSREQ | char[5] | Subsystem request | ||
| uncntunitcount | none | DALUNCNT | int | Device count | ||
| unit | UNIT= | DALUNIT | char[9] | Unit name |
Replace the corresponding lines in the table labeled, "Dynamic Allocation Inquiry Keywords," with the following entries:
| Identifier | JCL Equiv | SVC 99Key | Value | Format | Description | Notes |
|---|---|---|---|---|---|---|
| path | PATH= | DINRPATH | char[256] | HFS filename for which information is needed | (1) | |
| retpathcdisprtpathcdisprpathcdispretpcdisprtpcdisprpcdispretpcdsrtpcdsrpcdsretcndsrtcndsrcnds | returnPATHDISP=(n,c) | DINRPCDS | int* | Encoded | Return HFS file abnormal disposition |
Add the following lines to the table labeled, "Dynamic Allocation Inquiry Keywords:"
| Identifier | JCL Equiv | SVC 99Key | Value | Format | Description | Notes |
|---|---|---|---|---|---|---|
| retfdatretfiledatartfdatrfiledatartfdatrtfiledata | return FILEDATA= | DINRFDAT | int* | Encoded | Return TEXT/ BINARY attribute of HFS file | |
| rettyprettyperttyprttype | none | DINRTTYP | char* | Encoded | Return data set type | |
| retpathndispretpndispretpndsrpathndisprpndisprpndsrtpathndisprtpndisprtpnds | return PATHDISP= (n, ) | DINRPNDS | int* | Encoded | Return HFS file disposition | |
| retvolumeretvolserretvolrtvolumertvolserrtvol | return VOL=SER= | DINRTVOL | char(*) | [7] | Return first volume serial |
| Updates to the Socket Functions |
In Chapter 18, "Socket Function Reference," update the following sections as indicated:
selectecb
description to read:
The ecblist argument is the address of
an array of structures, each of which represents one or more contiguous _ecblist structures. Each structure contains two members,
a count of the number of ECBs, and the address of an array of ECBs. The count
may be zero, in which case the ECB array address is ignored.
setsocketopt description:
Note: TCP_NODELAY is not supported for non-integrated sockets. This is an IBM
restriction, and is not a SAS/C restriction. However, TCP_NODELAY is supported for OE (integrated)
sockets, which is the default for SAS/C Release 7.00. For releases prior to
7.00, you can use the setsockimp("OE") function
to get integrated sockets. ![[cautionend]](../common/images/cautend.gif)
| Update to getdtablesize Example |
In Chapter 18, "Socket Function Reference," replace the code in the "Example" section with the following code:
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
main()
{
int maxsockets;
fd_set *readset, *writeset, *exceptset);
int ready;
/* get maximum number of sockets */
maxsockets = getdtablesize();
/* allocate storage for fd sets (8 bits per byte, 4 byte int) */
readset = calloc((maxsockets+31)/32, 4);
writeset = calloc((maxsockets+31)/32, 4);
exceptset = calloc((maxsockets+31)/32, 4);
/* allocate storage for fd sets (8 bits per byte) */
.
.
.
ready = select(maxsockets, readset, writeset, exceptset, NULL);
/* wait for socket activity */
.
.
.
}
| New <sys/un.h> Header File |
In Chapter 15, "The BSD UNIX Socket Library," add the following information for the <sys/un.h> header file:
<sys/un.h> header file to
the list of header files:
17 <sys/un.h> |
The <sys/un.h> header file contains the definitions for UNIX domain sockets. <sys/socket.h> must be included in your code before <sys/un.h>.
sockaddr_un as illustrated
in the following example, is the UNIX domain socket address structure.
struct sockaddr_un { unsigned char sun_len; /* sockaddr len including null */ sa_family_t sun_family; /* AF_UNIX / AF_LOCAL */ char sun_path[104]; /* path name */ };
The family type constant AF_LOCAL has replaced the equivalent, historical constant AF_UNIX in more recent practice. However, both constants are defined in the header file <sys/socket.h>, and either one may be used.
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