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diff --git a/man-pages-posix-2013/man3p/fopen.3p b/man-pages-posix-2013/man3p/fopen.3p new file mode 100644 index 0000000..65a1f7d --- /dev/null +++ b/man-pages-posix-2013/man3p/fopen.3p @@ -0,0 +1,354 @@ +'\" et +.TH FOPEN "3P" 2013 "IEEE/The Open Group" "POSIX Programmer's Manual" +.SH PROLOG +This manual page is part of the POSIX Programmer's Manual. +The Linux implementation of this interface may differ (consult +the corresponding Linux manual page for details of Linux behavior), +or the interface may not be implemented on Linux. + +.SH NAME +fopen +\(em open a stream +.SH SYNOPSIS +.LP +.nf +#include <stdio.h> +.P +FILE *fopen(const char *restrict \fIpathname\fP, const char *restrict \fImode\fP); +.fi +.SH DESCRIPTION +The functionality described on this reference page is aligned with the +ISO\ C standard. Any conflict between the requirements described here and the +ISO\ C standard is unintentional. This volume of POSIX.1\(hy2008 defers to the ISO\ C standard. +.P +The +\fIfopen\fR() +function shall open the file whose pathname is the string pointed to by +.IR pathname , +and associates a stream with it. +.P +The +.IR mode +argument points to a string. If the string is one of the following, the +file shall be opened in the indicated mode. Otherwise, the behavior is +undefined. +.IP "\fIr\fP\ or\ \fIrb\fP" 14 +Open file for reading. +.IP "\fIw\fP\ or\ \fIwb\fP" 14 +Truncate to zero length or create file for writing. +.IP "\fIa\fP\ or\ \fIab\fP" 14 +Append; open or create file for writing at end-of-file. +.IP "\fIr+\fP\ or\ \fIrb+\fP\ or\ \fIr+b\fP" 14 +Open file for update (reading and writing). +.IP "\fIw+\fP\ or\ \fIwb+\fP\ or\ \fIw+b\fP" 14 +Truncate to zero length or create file for update. +.IP "\fIa+\fP\ or\ \fIab+\fP\ or\ \fIa+b\fP" 14 +Append; open or create file for update, writing at end-of-file. +.P +The character +.BR 'b' +shall have no effect, but is allowed for ISO\ C standard conformance. +Opening a file with read mode (\fIr\fP as the first character in the +.IR mode +argument) shall fail if the file does not exist or cannot be read. +.P +Opening a file with append mode (\fIa\fP as the first character in the +.IR mode +argument) shall cause all subsequent writes to the file to be forced to +the then current end-of-file, regardless of intervening calls to +\fIfseek\fR(). +.P +When a file is opened with update mode (\c +.BR '+' +as the second or third character in the +.IR mode +argument), both input and output may be performed on the associated +stream. However, the application shall ensure that output is not +directly followed by input without an intervening call to +\fIfflush\fR() +or to a file positioning function (\c +\fIfseek\fR(), +\fIfsetpos\fR(), +or +\fIrewind\fR()), +and input is not directly followed by output without an intervening +call to a file positioning function, unless the input operation +encounters end-of-file. +.P +When opened, a stream is fully buffered if and only if it can be +determined not to refer to an interactive device. The error and +end-of-file indicators for the stream shall be cleared. +.P +If +.IR mode +is \fIw\fR, \fIwb\fR, \fIa\fR, \fIab\fR, \fIw\fR+, \fIwb\fR+, +\fIw\fR+\fIb\fR, \fIa\fP+, \fIab\fR+, or \fIa\fR+\fIb\fR, and the file +did not previously exist, upon successful completion, +\fIfopen\fR() +shall mark for update the last data access, last data modification, and +last file status change timestamps of the file and the last file status +change and last data modification timestamps of the parent directory. +.P +If +.IR mode +is \fIw\fR, \fIwb\fR, \fIa\fR, \fIab\fR, \fIw\fR+, \fIwb\fR+, +\fIw\fR+\fIb\fR, \fIa\fP+, \fIab\fR+, or \fIa\fR+\fIb\fR, and the file +did not previously exist, the +\fIfopen\fR() +function shall create a file as if it called the +\fIcreat\fR() +function with a value appropriate for the +.IR path +argument interpreted from +.IR pathname +and a value of S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | +S_IWOTH for the +.IR mode +argument. +.P +If +.IR mode +is \fIw\fR, \fIwb\fR, \fIw\fR+, \fIwb\fR+, or \fIw\fR+\fIb\fR, and the +file did previously exist, upon successful completion, +\fIfopen\fR() +shall mark for update the last data modification and last file +status change timestamps of the file. +.P +After a successful call to the +\fIfopen\fR() +function, the orientation of the stream shall be cleared, +the encoding rule shall be cleared, +and the associated +.BR mbstate_t +object shall be set to describe an initial conversion state. +.P +The file descriptor associated with the opened stream shall be allocated +and opened as if by a call to +\fIopen\fR() +with the following flags: +.TS +center box tab(!); +cB | cB +l | l. +\fIfopen\fP(\^) Mode!\fIopen\fP(\^) Flags +_ +\fIr\fR or \fIrb\fR!O_RDONLY +\fIw\fR or \fIwb\fR!O_WRONLY|O_CREAT|O_TRUNC +\fIa\fR or \fIab\fR!O_WRONLY|O_CREAT|O_APPEND +\fIr+\fR or \fIrb+\fR or \fIr+b\fR!O_RDWR +\fIw+\fR or \fIwb+\fR or \fIw+b\fR!O_RDWR|O_CREAT|O_TRUNC +\fIa+\fR or \fIab+\fR or \fIa+b\fR!O_RDWR|O_CREAT|O_APPEND +.TE +.SH "RETURN VALUE" +Upon successful completion, +\fIfopen\fR() +shall return a pointer to the object controlling the stream. Otherwise, +a null pointer shall be returned, +and +.IR errno +shall be set to indicate the error. +.SH ERRORS +The +\fIfopen\fR() +function shall fail if: +.TP +.BR EACCES +Search permission is denied on a component of the path prefix, or the +file exists and the permissions specified by +.IR mode +are denied, or the file does not exist and write permission is denied +for the parent directory of the file to be created. +.TP +.BR EINTR +A signal was caught during +\fIfopen\fR(). +.TP +.BR EISDIR +The named file is a directory and +.IR mode +requires write access. +.TP +.BR ELOOP +A loop exists in symbolic links encountered during resolution of the +.IR path +argument. +.TP +.BR EMFILE +All file descriptors available to the process are currently open. +.TP +.BR EMFILE +{STREAM_MAX} +streams are currently open in the calling process. +.TP +.BR ENAMETOOLONG +.br +The length of a pathname exceeds +{PATH_MAX}, +or pathname resolution of a symbolic link produced an intermediate +result with a length that exceeds +{PATH_MAX}. +.TP +.BR ENFILE +The maximum allowable number of files is currently open in the system. +.TP +.BR ENOENT +The +.IR mode +string begins with +.BR 'r' +and a component of +.IR pathname +does not name an existing file, or +.IR mode +begins with +.BR 'w' +or +.BR 'a' +and a component of the path prefix of +.IR pathname +does not name an existing file, or +.IR pathname +is an empty string. +.TP +.BR ENOENT " or " ENOTDIR +.br +The +.IR pathname +argument contains at least one non-\c +<slash> +character and ends with one or more trailing +<slash> +characters. If +.IR pathname +names an existing file, an +.BR [ENOENT] +error shall not occur. +.TP +.BR ENOSPC +The directory or file system that would contain the new file cannot be +expanded, the file does not exist, and the file was to be created. +.TP +.BR ENOTDIR +A component of the path prefix names an existing file that is neither +a directory nor a symbolic link to a directory, or the +.IR pathname +argument contains at least one non-\c +<slash> +character and ends with one or more trailing +<slash> +characters and the last pathname component names an existing file that +is neither a directory nor a symbolic link to a directory. +.TP +.BR ENXIO +The named file is a character special or block special file, +and the device associated with this special file does not exist. +.TP +.BR EOVERFLOW +The named file is a regular file and the size of the file cannot be +represented correctly in an object of type +.BR off_t . +.TP +.BR EROFS +The named file resides on a read-only file system and +.IR mode +requires write access. +.P +The +\fIfopen\fR() +function may fail if: +.TP +.BR EINVAL +The value of the +.IR mode +argument is not valid. +.TP +.BR ELOOP +More than +{SYMLOOP_MAX} +symbolic links were encountered during resolution of the +.IR path +argument. +.TP +.BR EMFILE +{FOPEN_MAX} +streams are currently open in the calling process. +.TP +.BR ENAMETOOLONG +.br +The length of a component of a pathname is longer than +{NAME_MAX}. +.TP +.BR ENOMEM +Insufficient storage space is available. +.TP +.BR ETXTBSY +The file is a pure procedure (shared text) file that is being executed +and +.IR mode +requires write access. +.LP +.IR "The following sections are informative." +.SH EXAMPLES +.SS "Opening a File" +.P +The following example tries to open the file named +.BR file +for reading. The +\fIfopen\fR() +function returns a file pointer that is used in subsequent +\fIfgets\fR() +and +\fIfclose\fR() +calls. If the program cannot open the file, it just ignores it. +.sp +.RS 4 +.nf +\fB +#include <stdio.h> +\&... +FILE *fp; +\&... +void rgrep(const char *file) +{ +\&... + if ((fp = fopen(file, "r")) == NULL) + return; +\&... +} +.fi \fR +.P +.RE +.SH "APPLICATION USAGE" +None. +.SH RATIONALE +None. +.SH "FUTURE DIRECTIONS" +None. +.SH "SEE ALSO" +.IR "Section 2.5" ", " "Standard I/O Streams", +.IR "\fIcreat\fR\^(\|)", +.IR "\fIfclose\fR\^(\|)", +.IR "\fIfdopen\fR\^(\|)", +.IR "\fIfmemopen\fR\^(\|)", +.IR "\fIfreopen\fR\^(\|)", +.IR "\fIopen_memstream\fR\^(\|)" +.P +The Base Definitions volume of POSIX.1\(hy2008, +.IR "\fB<stdio.h>\fP" +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 7, Copyright (C) 2013 by the Institute of +Electrical and Electronics Engineers, Inc and The Open Group. +(This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the +event of any discrepancy between this version and the original IEEE and +The Open Group Standard, the original IEEE and The Open Group Standard +is the referee document. The original Standard can be obtained online at +http://www.unix.org/online.html . + +Any typographical or formatting errors that appear +in this page are most likely +to have been introduced during the conversion of the source files to +man page format. To report such errors, see +https://www.kernel.org/doc/man-pages/reporting_bugs.html . |