C Library Functions - uniq (3)

NAME

uniq(3f) - [M_io:QUERY] append a number to the end of filename to make a unique name if name exists (LICENSE:PD)

Synopsis
Description
Options
Returns
Examples
Author
License

SYNOPSIS

Usage

      character(len=:),allocatable function uniq(name,istart,verbose,create)
      character(len=*),intent(in) :: name
      integer,intent(in),optional :: istart
      logical,intent(in),optional :: verbose
      logical,intent(in),optional :: create

DESCRIPTION

Given a filename test if it is in use or exists. If it is, or if it ends in a period add a number to the end of the name and test if the new name exists. If necessary, increment the number and try again up to the value 9999999. By default an empty file is created if an unused name is found.

OPTIONS

name base input name used to create output filename If name ends in "." a numeric suffix is always added.

istart number to start with as a suffix. Default is 1. Must be a positive integer less than 9999999.

verbose
writes extra messages to stdout. Defaults to .false.

create create file if a new unused name is successfully found. Defaults to .true. .

RETURNS

uniq A unique filename that is the same as the NAME input parameter except with a number appended at the end if needed. If could not find a unique name a blank is returned.

EXAMPLES

Sample program

      program demo_uniq
      use M_io, only : uniq
      implicit none
      character(len=4096) :: myname
      integer             :: i
         myname=uniq(’does_not_exist’)
         write(*,*)’name stays the same   :’,trim(myname)
         open(unit=10,file=’does_exist’)
         myname=uniq(’does_exist’)
         write(*,*)’name has suffix added :’,trim(myname)
         do i=1,10
            myname=uniq(’does_exist’)
            write(*,*) ’FILENAME:’,trim(myname)
            open(unit=20+i,file=myname)
         enddo
      end program demo_uniq

Expected output

name stays the same does_not_exist name has suffix added does_exist0001 FILENAME:does_exist0002 FILENAME:does_exist0003 FILENAME:does_exist0004 FILENAME:does_exist0005 FILENAME:does_exist0006 FILENAME:does_exist0007 FILENAME:does_exist0008 FILENAME:does_exist0009 FILENAME:does_exist0010 FILENAME:does_exist0011

AUTHOR

John S. Urban, 1993

LICENSE

Public Domain

Nemo Release 3.1

uniq (3)

June 29, 2025

Generated by manServer 1.08 from 30a1b3c7-cb53-4329-a2a8-9f0e17bc8ea0 using man macros.

name	base input name used to create output filename If name ends in "." a numeric suffix is always added.
istart	number to start with as a suffix. Default is 1. Must be a positive integer less than 9999999.
verbose
	writes extra messages to stdout. Defaults to .false.
create	create file if a new unused name is successfully found. Defaults to .true. .