The author claims that his awk script will print out all the limits for

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Asked: May 27, 20262026-05-27T14:38:00+00:00 2026-05-27T14:38:00+00:00

The author claims that his awk script will print out all the limits for

0

The author claims that his awk script will print out all the limits for a POSIX.1 and XSI compliant system. I am using Red Hat Enterprise Linux Server release 6.0 (Santiago). When I run his awk script it does not seem to be printing out the #ifdef portion of the C program. My thoughts are that sysconf.sym do not exist on this distribution, therefore the while loops never run. Could someone please confirm that? If this is the case what changes would I need to make to the awk script to get it to print out the #ifdef portion of the code? The awk script is:

# Run with awk -f <awk_script>

BEGIN   {
    printf("#include \"apue.h\"\n")
    printf("#include <errno.h>\n")
    printf("#include <limits.h>\n")
    printf("#include <stdio.h>\n")
    printf("\n")

    printf("int log_to_stderr = 0;\n")

    printf("static void pr_sysconf(char *, int);\n")
    printf("static void pr_pathconf(char *, char *, int);\n")
    printf("\n")
    printf("int\n")
    printf("main(int argc, char *argv[])\n")
    printf("{\n")
    printf(" if (argc != 2)\n")
    printf("  err_quit(\"usage: a.out <dirname>\");\n\n")
    FS="\t+"
    while (getline <"sysconf.sym" > 0) {
        printf("#ifdef %s\n", $1)
        printf(" printf(\"%s defined to be %%d\\n\", %s+0);\n", $1, $1)
        printf("#else\n")
        printf(" printf(\"no symbol for %s\\n\");\n", $1)
        printf("#endif\n")
        printf("#ifdef %s\n", $2)
        printf(" pr_sysconf(\"%s =\", %s);\n", $1, $2)
        printf("#else\n")
        printf(" printf(\"no symbol for %s\\n\");\n", $2)
        printf("#endif\n")
    }
    close("sysconf.sym")
    while (getline <"pathconf.sym" > 0) {
        printf("#ifdef %s\n", $1)
        printf(" printf(\"%s defined to be %%d\\n\", %s+0);\n", $1, $1)
        printf("#else\n")
        printf(" printf(\"no symbol for %s\\n\");\n", $1)
        printf("#endif\n")
        printf("#ifdef %s\n", $2)
        printf(" pr_pathconf(\"%s =\", argv[1], %s);\n", $1, $2)
        printf("#else\n")
        printf(" printf(\"no symbol for %s\\n\");\n", $2)
        printf("#endif\n")
    }
    close("pathconf.sym")
    exit
}
END {
    printf(" exit(0);\n")
    printf("}\n\n")
    printf("static void\n")
    printf("pr_sysconf(char *mesg, int name)\n")
    printf("{\n")
    printf(" long val;\n\n")
    printf(" fputs(mesg, stdout);\n")
    printf(" errno = 0;\n")
    printf(" if ((val = sysconf(name)) < 0) {\n")
    printf("  if (errno != 0) {\n")
    printf("   if (errno == EINVAL)\n")
    printf("    fputs(\" (not supported)\\n\", stdout);\n")
    printf("   else\n")
    printf("    err_sys(\"sysconf error\");\n")
    printf("  } else {\n")
    printf("   fputs(\" (no limit)\\n\", stdout);\n")
    printf("  }\n")
    printf(" } else {\n")
    printf("  printf(\" %%ld\\n\", val);\n")
    printf(" }\n")
    printf("}\n\n")
    printf("static void\n")
    printf("pr_pathconf(char *mesg, char *path, int name)\n")
    printf("{\n")
    printf(" long val;\n")
    printf("\n")
    printf(" fputs(mesg, stdout);\n")
    printf(" errno = 0;\n")
    printf(" if ((val = pathconf(path, name)) < 0) {\n")
    printf("  if (errno != 0) {\n")
    printf("   if (errno == EINVAL)\n")
    printf("    fputs(\" (not supported)\\n\", stdout);\n")
    printf("   else\n")
    printf("    err_sys(\"pathconf error, path = %%s\", path);\n")
    printf("  } else {\n")
    printf("   fputs(\" (no limit)\\n\", stdout);\n")
    printf("  }\n")
    printf(" } else {\n")
    printf("  printf(\" %%ld\\n\", val);\n")
    printf(" }\n")
    printf("}\n")
}

Update

If you would like the apue.h header so you can compile the C program that can be found at.
apue.h