NAG FL Interface
x04bbf (line_​read)

1 Purpose

x04bbf reads a single formatted record from an external file.

2 Specification

Fortran Interface
Subroutine x04bbf ( nin, recin, ifail)
Integer, Intent (In) :: nin
Integer, Intent (Inout) :: ifail
Character (*), Intent (Out) :: recin
C Header Interface
#include <nag.h>
void  x04bbf_ (const Integer *nin, char *recin, Integer *ifail, const Charlen length_recin)
The routine may be called by the names x04bbf or nagf_file_line_read.

3 Description

x04bbf is used by NAG Library routines to read formatted records from an external file. All formatted input from an external file by NAG Library routines is performed by calls to x04bbf.

4 References


5 Arguments

1: nin Integer Input
On entry: the Fortran unit number which identifies the file to be read from. If nin<0 (not a valid Fortran unit number), then no input occurs.
2: recin Character(*) Output
On exit: the first lenrecin characters of the record read from unit nin, padded with trailing blanks if the record was shorter than lenrecin.
3: ifail Integer Input/Output
On entry: ifail must be set to 0, -1 or 1 to set behaviour on detection of an error; these values have no effect when no error is detected.
A value of 0 causes the printing of an error message and program execution will be halted; otherwise program execution continues. A value of -1 means that an error message is printed while a value of 1 means that it is not.
If halting is not appropriate, the value -1 or 1 is recommended. If message printing is undesirable, then the value 1 is recommended. Otherwise, the value 0 is recommended. When the value -1 or 1 is used it is essential to test the value of ifail on exit.
On exit: ifail=0 unless the routine detects an error or a warning has been flagged (see Section 6).

6 Error Indicators and Warnings

If on entry ifail=0 or -1, explanatory error messages are output on the current error message unit (as defined by x04aaf).
Errors or warnings detected by the routine:
End-of-file or reading error detected in a READ statement.
An unexpected error has been triggered by this routine. Please contact NAG.
See Section 7 in the Introduction to the NAG Library FL Interface for further information.
Your licence key may have expired or may not have been installed correctly.
See Section 8 in the Introduction to the NAG Library FL Interface for further information.
Dynamic memory allocation failed.
See Section 9 in the Introduction to the NAG Library FL Interface for further information.

7 Accuracy

Not applicable.

8 Parallelism and Performance

x04bbf is not threaded in any implementation.

9 Further Comments


10 Example

This example program simply illustrates how a formatted record is read from the NAG Library, by first reading it into the character-string recin, used as an internal file, by x04bbf and then reading the internal file.

10.1 Program Text

Program Text (x04bbfe.f90)

10.2 Program Data

Program Data (x04bbfe.d)

10.3 Program Results

Program Results (x04bbfe.r)