Error codes (symbolic names and values) are common to both C/C++ and Fortran 90 API. Whenever text in the following table mentions C/C++ function, the same holds for its Fortran 90 equivalent.
| Error Symbol | Code | Error Description |
| ISDC_OK | 0 | No error |
| PIL_OK | 0 | No error (alias of ISDC_OK) |
| PIL_NUL_PTR | -3000 | Null pointer passed as an argument, and function does not allow it. Can appear in many situations. For example passing NULL as a name of argument or passing NULL as a pointer to result variable causes PILGetXXX function to return this error code. |
| PIL_BAD_ARG | -3001 | Bad argument passed. This error may be returned in many situations. Usually means that data type is incorrect, i.e. calling PILGetInt("a",..) when parameter "a" is of type string. Also when check for file access mode fails (PILGetFname) this error is returned. When PIL_QUERY_OVERRIDE mode is in effect and default value of parameter is out of range or invalid this error is returned (PILGetXXX) This error may also mean internal PIL error. |
| PIL_NO_MEM | -3002 | Not enough memory. Means that PIL library was not able to allocate sufficient memory to handle request. This kind of error is very unlikely to happen, since PIL allocates very small amounts of memory. If it happens it probably means that memory is overwritten by process or machine (operating system) is not in good shape. |
| PIL_NO_FILE | -3003 | Cannot open/create file. This error may be returned by PILInit when parameter file cannot be found/created/copied/updated and by PILgetFname when testing for files existence. |
| PIL_ERR_FREAD | -3004 | Read from file failed. Means physical disk i/o error, lock problem, or network problem when parameter file resides on NFS mounted partition. This error may be returned by PILInit, PILFlushParameters, PILReloadParameters, PILClose |
| PIL_ERR_FWRITE | -3005 | Write to file failed. Means physical disk i/o error, disk full, lock problem, or network problem when parameter file resides on NFS mounted partition. This error may be returned by PILInit, PILFlushParameters, PILReloadParameters, PILClose |
| Error Symbol | Code | Error Description |
| PIL_EOS | -3006 | Unexpected end of string. This error means that given line in parameter file is badly formatted and does not contain 7 fields separated by ','. This error is handled internally by PIL library and should never be returned to user, since PIL library ignores all badly formatted lines in parameter files. |
| PIL_BAD_NAME | -3007 | Invalid name of parameter. This error means that name of parameter found in parameter file contains invalid characters (ASCII-7 only are allowed). |
| PIL_BAD_TYPE | -3008 | Invalid type of parameter in parameter file. This error means that PIL was not able to decode parameter type. Probably parameter file is badly formatted. |
| PIL_BAD_MODE | -3009 | Invalid mode of parameter in parameter file. This error means that PIL was not able to decode parameter mode. Probably parameter file is badly formatted. |
| PIL_BAD_LINE | -3010 | Invalid line in parameter file encountered. This error means that format of line in parameter file does not even resemble correct one. |
| PIL_NOT_IMPLEMENTED | -3011 | Feature not implemented. This error means that type/mode/indirection type is valid (according to IRAF/XPI standard) but PIL library does not implement this. Example of unimplemented feature is indirection of data from other parameter files. |
| PIL_FILE_NOT_EXIST | -3012 | File does not exist. Included for compatibility reasons. Version 1.0 of PIL does not return this error. |
| PIL_FILE_EXIST | -3013 | File exists. Included for compatibility reasons. Version 1.0 of PIL does not return this error. |
| PIL_FILE_NO_RD | -3014 | File is not readable. Check file access permission/ownership and mount options. |
| PIL_FILE_NO_WR | -3015 | File is not writable. Check file access permission/ownership and mount options. By default PIL requires READWRITE access to the parameter file. |
| PIL_LINE_BLANK | -3016 | Blank line encountered. Handled internally by PIL. Never returned to user. |
| PIL_LINE_COMMENT | -3017 | Comment line encountered. Handled internally by PIL. Never returned to user. |
| PIL_LINE_ERROR | -3018 | Invalid line encountered. Handled internally by PIL. Never returned to user. |
| Error Symbol | Code | Error Description |
| PIL_NOT_FOUND | -3019 | No such parameter. This error means that no parameter of given name is in parameter file. |
| PIL_PFILES_TOO_LONG | -3020 | PFILES environment variable too long. Included for compatibility reasons. Version 1.0 of PIL does not return this error. |
| PIL_PFILES_FORMAT | -3021 | PFILES environment variable is badly formatted. Included for compatibility reasons. Version 1.0 of PIL does not return this error. |
| PIL_LOCK_FAILED | -3022 | Cannot (un)lock parameter file. This error means that PIL library couldn't obtain exclusive access to file (by locking it). Operation still was performed, by consistency of data od disk is not assured. |
| PIL_BOGUS_CMDLINE | -3023 | Bogus parameters found in command line. In other words some of parameter names specified in command line do not have their counterparts in parameter file. This error may be returned by PILVerifyCmdLine(). |
| PIL_NO_LOGGER | -3024 | Error code used internally by PIL to signal that no logger function has been registered. |
| PIL_LINE_TOO_MANY | -3025 | Format error in parameter file. Too many (>7) comma separated items found. |
| PIL_LINE_TOO_FEW | -3026 | Format error in parameter file. Too few (<7) comma separated items found. |
| PIL_LINE_UNMATCHED_QUOTE | -3027 | Format error in parameter file. Unbalanced quote or doublequote character found. |
| PIL_LINE_NO_LF | -3028 | Format error in parameter file. No terminating LineFeed character found. |
| PIL_LINE_EXTRA_SPACES | -3029 | Format error in parameter file. Extra spaces following closing quote or doublequote character found. found. |
| PIL_BAD_VAL_BOOL | -3030 | Cannot convert string to boolean value. Expecting either yes or no string. |
| PIL_BAD_VAL_INT | -3031 | Cannot convert string to integer value. Expecting [+-]dddddd format |
| PIL_BAD_VAL_REAL | -3032 | Cannot convert string to real value. Expecting [+-]ddd[.ddd][e[+-ddd]] format |
| PIL_BAD_VAL_INT_VAR_VECTOR | -3033 | Cannot convert string to a vector of integers. Expecting space separated list of integer numbers. |
| PIL_BAD_VAL_INT_VECTOR | -3034 | Cannot convert string to a vector of integers. Expecting space separated list of integer numbers. This error is also returned when number of integers found in the string does not correspond to the number given in a call to PILGetIntVector(); |
| PIL_BAD_VAL_REAL_VAR_VECTOR | -3035 | Cannot convert string to a vector of reals. Expecting space separated list of real numbers. |
| PIL_BAD_VAL_REAL_VECTOR | -3036 | Cannot convert string to a vector of reals. Expecting space separated list of real numbers. This error is also returned when number of reals found in the string does not correspond to the number given in a call to PILGetRealVector() or PILGetReal4Vector(). |
| PIL_OFF_RANGE | -3037 | Value is off limits set by min and max fields. This error may be returned when PIL_QUERY_OVERRIDE mode is in effect. |
| PIL_BAD_ENUM_VALUE | -3038 | Value does not match any value from enumerated list (min field). This error may be returned when PIL_QUERY_OVERRIDE mode is in effect. |
| PIL_BAD_FILE_ACCESS | -3039 | Effective file access mode does not match the one specified in parameter type (i.e. file is not readable when type is "fr"). This error may be returned when PIL_QUERY_OVERRIDE mode is in effect. |