Additional PRO/5 Command Information For the UNIX Operating System

Overview

The following contains useful information about additional modes supported or not supported on the UNIX operating system version of PRO/5.

Shell Command

The "!" character, in console mode only, allows execution of UNIX OS commands. For example, would generate a listing of the current directory by passing all text after the "!" to the current UNIX shell:

!ls *

PRO/5 does not examine or modify in any way the text following the "!" character.

CISAM

PRO/5 supports an additional file type (called C-ISAM) on systems that provide a library for accessing and manipulating this file type. As of this writing, the run-time modules for INFORMIX C-ISAM files are required. (The READ.ME file will document linkage to other C-ISAM libraries, if that should occur.)

FID(0)

If the environment string BBTERM=name exists, then the FID(0) will return this string. You may also use the -t flag. See Invoking PRO/5, Command Line Options for more information.

If the standard input and standard output for PRO/5 are not the same device or the "tty" device, then the FID(0) will be the alias "IO."

In all other cases, the FID(0) will be the first ALIAS found that references the current "tty" device.

RENAME

PRO/5 will attempt to rename a file from one path to another. However, a file usually cannot be given a new path that goes to a different disk drive than the old path.

If the new file name does not have a path, the path from the original file name is used.

SCALL()

The SCALL() function may fail to execute when the current process cannot create another process, (using the "fork(2)" system call). In this instance, PRO/5 will issue an !ERROR=16.

SETTIME

SETTIME will only affect the UNIX system clock if you have superuser privileges. In all other cases, PRO/5 will issue an !ERROR=18.

TCB(10)

The TCB(10) will return an error code indicating the underlying cause of an error generated in PRO/5 input or output. If the value returned by TCB(10) is positive, the value contains no more information than the ERR variable. If TCB(10) returns a negative number, the ABS() of the value is the actual error code given to the PRO/5 filesystem.

The value of the TCB(10) function will not change until the application causes another error to occur using I/O. The value of the TCB(10) relates only to errors involving files or devices.

Application code depending on the values returned by the TCB(10) function will be highly non-portable as these returned values may change between host operating system releases and/or PRO/5 releases.