Fortran User's Guide

Appendix A Runtime Error Messages

This appendix describes the error messages generated by the Fortran I/O library, signal handler, and operating system.

Operating System Error Messages

Operating system error messages include system call failures, C library errors, and shell diagnostics. The system call error messages are found in intro(2). System calls made through the Fortran library do not produce error messages directly. The following system routine in the Fortran library calls C library routines which produce an error message:

	CALL SYSTEM("rm /") 
	END

The following message is displayed:

rm: / directory

Signal Handler Error Messages

Before beginning execution of a program, the Fortran library sets up a signal handler (sigdie) for signals that can cause termination of the program. sigdie prints a message that describes the signal, flushes any pending output, and generates a core image and a traceback.

Presently, the only arithmetic exception that produces an error message is the INTEGER*2 division with a denominator of zero. All other arithmetic exceptions are ignored.

A signal handler error example follows, where the subroutine SUB tries to access parameters that are not passed to it:

	CALL SUB() 
	END 
	SUBROUTINE SUB(I,J,K) 
	I=J+K 
	RETURN 
	END

The following error message results:

*** Segmentation violation
Illegal instruction (core dumped)

I/O Error Messages (f77)

The error messages in this section are generated by the Fortran 77 I/O library. The error numbers are returned in the IOSTAT variable if the ERR return is taken.

For example, the following program tries to do an unformatted write to a file opened for formatted output:

      WRITE( 6 ) 1 
      END

and produces error messages like the following:

sue: [1003] unformatted io not allowed
logical unit 6, named 'stdout'
lately: writing sequential unformatted external IO

The following error messages are generated. These same messages are also documented at the end of the man page perror(3F).

If the error number is less than 1000, then it is a system error. See intro (2).

Table A-1 f77 Runtime I/O Messages


Error	Message
`1000`	`error in format` Read the error message output for the location of the error in the format. It can be caused by more than 10 levels of nested parentheses or an extremely long format statement.
`1001`	`illegal unit number` It is illegal to close logical unit 0. Negative unit numbers are not allowed. The upper limit is 2³¹ - 1.
`1002`	`formatted io not allowed` The logical unit was opened for unformatted I/O.
`1003`	`unformatted io not allowed` The logical unit was opened for formatted I/O.
`1004`	`direct io not allowed` The logical unit was opened for sequential access, or the logical record length was specified as 0.
`1005`	`sequential io not allowed` The logical unit was opened for direct access I/O.
`1006`	`can't backspace file` You cannot do a `seek` on the file associated with the logical unit; therefore, you cannot backspace. The file may be a `tty` device or a pipe.
`1007`	`off beginning of record` You tried to do a left tab to a position before the beginning of an internal input record.
`1008`	`can't stat file` The system cannot return status information about the file. Perhaps the directory is unreadable.
`1009`	`no * after repeat count` Repeat counts in list-directed I/O must be followed by an `*` with no blank spaces.
1010	`off end of record` A formatted write tried to go beyond the logical end-of-record. An unformatted read or write also causes this
1011	<Not used>
1012	`incomprehensible list input` List input has to be as specified in the declaration.
1013	`out of free space` The library dynamically creates buffers for internal use. You ran out of memory for them; that is, your program is too big.
1014	`unit not connected` The logical unit was not open.
1015	`read unexpected character` Certain format conversions cannot tolerate nonnumeric data.
1016	`illegal logical input field` logical data must be T or F.
1017	`'new' file exists` You tried to open an existing file with status='new'.
1018	`can't find 'old' file` You tried to open a nonexistent file with status='old'.
1019	`unknown system error` This error should not happen, but..
1020	`requires seek ability` Attempted a `seek` on a file that does not allow it. I/O operation requiring a `seek` are direct access, sequential unformatted I/O, and tabbing left.
1021	`illegal argument` Certain arguments to open and related functions are checked for legitimacy. Often only nondefault forms are checked
1022	`negative repeat count` The repeat count for list-directed input must be a positive integer.
1023	`illegal operation for unit` Attempted an I/O operation that is not possible for the device associated with the logical unit. You get this error if you try to read past end-of-tape, or end-of-file.
1024	<Not used>
1025	`incompatible specifiers in open` Attempted to open a file with the 'new' option and the access='append' option, or some other invalid combination.
1026	`illegal input for namelist` A namelist read encountered an invalid data item.
1027	`error in FILEOPT parameter` The `FILEOPT` string in an `OPEN` statement has bad syntax.
1028	`WRITE to readonly file` Attempt to write on a unit that was opened for reading only.
1029	`READ from writeonly file` Attempt to read from a unit that was opened for writing only.
1030	`overflow converting numeric input` Integer input data is too large for the corresponding input variable
1032	`exponent overflow on numeric input` The floating-point input data is too large to be represented by the corresponding input variable.

I/O Error Messages (f90)

This is a partial list of runtime I/O messages issued by f90

Table A-2 f90 Runtime I/O Messages


Error	Message
1000	format error
1001	illegal unit number
1002	formatted I/O on unformatted unit
1003	unformatted I/O on formatted unit
1004	direct-access I/O on sequential-access unit
1005	sequential-access I/O on direct-access unit
1006	device does not support BACKSPACE
1007	off beginning of record
1008	can't stat file
1009	no * after repeat count
1010	record too long
1011	truncation failed
1012	incomprehensible list input
1013	out of free space
1014	unit not connected
1015	read unexpected character
1016	illegal logical input field
1017	`new' file exists
1018	can't find `old' file
1019	unknown system error
1020	requires seek ability
1021	illegal argument
1022	negative repeat count
1023	illegal operation for channel or device
1024	reentrant I/O
1025	incompatible specifiers in open
1026	illegal input for namelist
1027	error in FILEOPT parameter
1028	writing not allowed
1029	reading not allowed
1030	integer overflow on input
1031	floating-point overflow on input
1032	floating-point underflow on input
1051	default input unit closed
1052	default output unit closed
1053	direct-access READ from unconnected unit
1054	direct-access WRITE to unconnected unit
1055	unassociated internal unit
1056	null reference to internal unit
1057	empty internal file
1058	list-directed I/O on unformatted unit
1059	namelist I/O on unformatted unit
1060	tried to write past end of internal file
1061	unassociated ADVANCE specifier
1062	ADVANCE specifier is not `YES' or `NO'
1063	EOR specifier present for advancing input
1064	SIZE specifier present for advancing input
1065	negative or zero record number
1066	record not in file
1067	corrupted format
1068	unassociated input variable
1069	more I/O-list items than data edit descriptors
1070	zero stride in subscript triplet
1071	zero step in implied DO-loop
1072	negative field width
1073	zero-width field
1074	character string edit descriptor reached on input
1075	Hollerith edit descriptor reached on input
1076	no digits found in digit string
1077	no digits found in exponent
1078	scale factor out of range
1079	digit equals or exceeds radix
1080	unexpected character in integer field
1081	unexpected character in real field
1082	unexpected character in logical field
1083	unexpected character in integer value
1084	unexpected character in real value
1085	unexpected character in complex value
1086	unexpected character in logical value
1087	unexpected character in character value
1088	unexpected character before NAMELIST group name
1089	NAMELIST group name does not match the name in the program
1090	unexpected character in NAMELIST item
1091	unmatched parenthesis in NAMELIST item name
1092	variable not in NAMELIST group
1093	too many subscripts in NAMELIST object name
1094	not enough subscripts in NAMELIST object name
1095	zero stride in NAMELIST object name
1096	empty section subscript in NAMELIST object name
1097	subscript out of bounds in NAMELIST object name
1098	empty substring in NAMELIST object name
1099	substring out of range in NAMELIST object name
1100	unexpected component name in NAMELIST object name
1111	unassociated ACCESS specifier
1112	unassociated ACTION specifier
1113	unassociated BINARY specifier
1114	unassociated BLANK specifier
1115	unassociated DELIM specifier
1116	unassociated DIRECT specifier
1117	unassociated FILE specifier
1118	unassociated FMT specifier
1119	unassociated FORM specifier
1120	unassociated FORMATTED specifier
1121	unassociated NAME specifier
1122	unassociated PAD specifier
1123	unassociated POSITION specifier
1124	unassociated READ specifier
1125	unassociated READWRITE specifier
1126	unassociated SEQUENTIAL specifier
1127	unassociated STATUS specifier
1128	unassociated UNFORMATTED specifier
1129	unassociated WRITE specifier
1130	zero length file name
1131	ACCESS specifier is not `SEQUENTIAL' or `DIRECT'
1132	ACTION specifier is not `READ', `WRITE' or `READWRITE'
1133	BLANK specifier is not `ZERO' or `NULL'
1134	DELIM specifier is not `APOSTROPHE', `QUOTE', or `NONE'
1135	unexpected FORM specifier
1136	PAD specifier is not `YES' or `NO'
1137	POSITION specifier is not `APPEND', `ASIS', or `REWIND'
1138	RECL specifier is zero or negative
1139	no record length specified for direct-access file
1140	unexpected STATUS specifier
1141	status is specified and not `OLD' for connected unit
1142	STATUS specifier is not `KEEP' or `DELETE'
1143	status `KEEP' specified for a scratch file
1144	impossible status value
1145	a file name has been specified for a scratch file
1146	attempting to open a unit that is being read from or written to
1147	attempting to close a unit that is being read from or written to
1148	attempting to open a directory
1149	status is `OLD' and the file is a dangling symbolic link
1150	status is `NEW' and the file is a symbolic link
1151	no free scratch file names
1161	device does not support REWIND
1162	read permission required for BACKSPACE
1163	BACKSPACE on direct-access unit
1164	BACKSPACE on binary unit
1165	end-of-file seen while backspacing
1166	write permission required for ENDFILE
1167	ENDFILE on direct-access unit
1181	attempting to allocate an allocated array
1182	deallocating an unassociated pointer
1183	deallocating an unallocated allocatable array
1184	deallocating an allocatable array through a pointer
1185	deallocating an object not allocated by an ALLOCATE statement
1186	deallocating a part of an object
1187	deallocating a larger object than was allocated
1191	unallocated array passed to array intrinsic function
1192	illegal rank
1193	small source size
1194	zero array size
1195	negative elements in shape
1196	illegal kind
1197	nonconformable array
2001	invalid constant, structure, or component name
2002	handle not created
2003	character argument too short
2004	array argument too long or too short
2005	end of file, record, or directory stream